Sulphur dioxide and coal, annual growth rate in Spain
Spain: Sulphur dioxide and coal, annual growth rate was 9.33 % change on previous year in 2022. ◆ Volatile
Sulphur dioxide and coal, annual growth rate in Spain, 1751–2022
Source: Statizoid (derived). Measured in % change on previous year.
Analysis
Spain recorded 9.33 % change on previous year for sulphur dioxide and coal, annual growth rate in 2022.
That represents a change of up 13.3% on the previous year and up 379.9% over ten years.
Over the whole period, sulphur dioxide and coal, annual growth rate in Spain peaked at 117.35 % change on previous year in 1938 and was at its lowest, -62.42 % change on previous year, in 1936.
Spain ranks 51st of 219 countries on this measure, in the top quarter.
The series is highly variable year to year, so single readings are best treated with caution.
Sulphur dioxide and coal, annual growth rate in Spain, year by year
| Year | % change on previous year | Change |
|---|---|---|
| 1751 | 0.1044 % change on previous year | — |
| 1752 | 0.1036 % change on previous year | -0.7% |
| 1753 | 0.1022 % change on previous year | -1.4% |
| 1754 | 0.1015 % change on previous year | -0.7% |
| 1755 | 0.1004 % change on previous year | -1.1% |
| 1756 | 0.0993 % change on previous year | -1.1% |
| 1757 | 0.0983 % change on previous year | -1.1% |
| 1758 | 0.0972 % change on previous year | -1.1% |
| 1759 | 0.0961 % change on previous year | -1.1% |
| 1760 | 0.0951 % change on previous year | -1.1% |
| 1761 | 0.1014 % change on previous year | +6.7% |
| 1762 | 0.1004 % change on previous year | -1.1% |
| 1763 | 0.0996 % change on previous year | -0.7% |
| 1764 | 0.0982 % change on previous year | -1.4% |
| 1765 | 0.0972 % change on previous year | -1.1% |
| 1766 | 0.0961 % change on previous year | -1.1% |
| 1767 | 0.0954 % change on previous year | -0.8% |
| 1768 | 0.094 % change on previous year | -1.4% |
| 1769 | 0.093 % change on previous year | -1.1% |
| 1770 | 0.0919 % change on previous year | -1.1% |
| 1771 | 0.0985 % change on previous year | +7.2% |
| 1772 | 0.0972 % change on previous year | -1.4% |
| 1773 | 0.0961 % change on previous year | -1.1% |
| 1774 | 0.0951 % change on previous year | -1.1% |
| 1775 | 0.0944 % change on previous year | -0.8% |
| 1776 | 0.0927 % change on previous year | -1.8% |
| 1777 | 0.092 % change on previous year | -0.8% |
| 1778 | 0.0909 % change on previous year | -1.1% |
| 1779 | 0.0899 % change on previous year | -1.1% |
| 1780 | 0.0885 % change on previous year | -1.5% |
| 1781 | 0.0951 % change on previous year | +7.4% |
| 1782 | 0.0941 % change on previous year | -1.1% |
| 1783 | 0.093 % change on previous year | -1.1% |
| 1784 | 0.0917 % change on previous year | -1.4% |
| 1785 | 0.091 % change on previous year | -0.8% |
| 1786 | 0.0896 % change on previous year | -1.5% |
| 1787 | 0.0886 % change on previous year | -1.1% |
| 1788 | 0.0873 % change on previous year | -1.5% |
| 1789 | 0.0866 % change on previous year | -0.8% |
| 1790 | 0.0852 % change on previous year | -1.5% |
| 1791 | 0.0917 % change on previous year | +7.6% |
| 1792 | 0.0907 % change on previous year | -1.1% |
| 1793 | 0.0894 % change on previous year | -1.5% |
| 1794 | 0.0884 % change on previous year | -1.1% |
| 1795 | 0.0874 % change on previous year | -1.1% |
| 1796 | 0.0863 % change on previous year | -1.2% |
| 1797 | 0.085 % change on previous year | -1.5% |
| 1798 | 0.084 % change on previous year | -1.2% |
| 1799 | 0.083 % change on previous year | -1.2% |
| 1800 | 0.0817 % change on previous year | -1.6% |
| 1801 | 0.0882 % change on previous year | +7.9% |
| 1802 | 0.0871 % change on previous year | -1.1% |
| 1803 | 0.0861 % change on previous year | -1.2% |
| 1804 | 0.0848 % change on previous year | -1.5% |
| 1805 | 0.0835 % change on previous year | -1.5% |
| 1806 | 0.0828 % change on previous year | -0.8% |
| 1807 | 0.0815 % change on previous year | -1.6% |
| 1808 | 0.0802 % change on previous year | -1.6% |
| 1809 | 0.0792 % change on previous year | -1.2% |
| 1810 | 0.0783 % change on previous year | -1.2% |
| 1811 | 0.0847 % change on previous year | +8.2% |
| 1812 | 0.0834 % change on previous year | -1.5% |
| 1813 | 0.0824 % change on previous year | -1.2% |
| 1814 | 0.0811 % change on previous year | -1.6% |
| 1815 | 0.0801 % change on previous year | -1.2% |
| 1816 | 0.0788 % change on previous year | -1.6% |
| 1817 | 0.0778 % change on previous year | -1.2% |
| 1818 | 0.0768 % change on previous year | -1.3% |
| 1819 | 0.0755 % change on previous year | -1.7% |
| 1820 | 0.0743 % change on previous year | -1.7% |
| 1821 | 0.4889 % change on previous year | +558.4% |
| 1822 | 0.4838 % change on previous year | -1.0% |
| 1823 | 0.4788 % change on previous year | -1.0% |
| 1824 | 0.4741 % change on previous year | -1.0% |
| 1825 | 0.4689 % change on previous year | -1.1% |
| 1826 | 0.4643 % change on previous year | -1.0% |
| 1827 | 0.4595 % change on previous year | -1.0% |
| 1828 | 0.4547 % change on previous year | -1.0% |
| 1829 | 0.45 % change on previous year | -1.0% |
| 1830 | 1.54 % change on previous year | +241.1% |
| 1831 | 6.78 % change on previous year | +341.6% |
| 1832 | 6.27 % change on previous year | -7.6% |
| 1833 | 5.98 % change on previous year | -4.6% |
| 1834 | 5.56 % change on previous year | -6.9% |
| 1835 | 5.34 % change on previous year | -4.0% |
| 1836 | 9.02 % change on previous year | +68.8% |
| 1837 | 7.6 % change on previous year | -15.8% |
| 1838 | 2.21 % change on previous year | -70.9% |
| 1839 | 8.25 % change on previous year | +272.5% |
| 1840 | 2 % change on previous year | -75.7% |
| 1841 | 16.1 % change on previous year | +704.8% |
| 1842 | 10.17 % change on previous year | -36.8% |
| 1843 | 7.85 % change on previous year | -22.8% |
| 1844 | 7.24 % change on previous year | -7.8% |
| 1845 | 11.67 % change on previous year | +61.2% |
| 1846 | 3.87 % change on previous year | -66.8% |
| 1847 | 0.8687 % change on previous year | -77.6% |
| 1848 | 6.14 % change on previous year | +607.2% |
| 1849 | 5.76 % change on previous year | -6.3% |
| 1850 | 13.81 % change on previous year | +139.8% |
| 1851 | 4.12 % change on previous year | -70.2% |
| 1852 | 4.69 % change on previous year | +14.0% |
| 1853 | 10.65 % change on previous year | +126.8% |
| 1854 | -3.8 % change on previous year | -135.7% |
| 1855 | 2.78 % change on previous year | -173.3% |
| 1856 | 14.41 % change on previous year | +417.5% |
| 1857 | 6.78 % change on previous year | -53.0% |
| 1858 | 16.04 % change on previous year | +136.6% |
| 1859 | 20.75 % change on previous year | +29.4% |
| 1860 | 10.8 % change on previous year | -47.9% |
| 1861 | 2.54 % change on previous year | -76.5% |
| 1862 | 5.49 % change on previous year | +116.1% |
| 1863 | 6.61 % change on previous year | +20.6% |
| 1864 | -2.3 % change on previous year | -134.8% |
| 1865 | -0.595 % change on previous year | -74.2% |
| 1866 | 1.43 % change on previous year | -340.2% |
| 1867 | 8.25 % change on previous year | +477.3% |
| 1868 | 4 % change on previous year | -51.5% |
| 1869 | 1.21 % change on previous year | -69.8% |
| 1870 | 11.2 % change on previous year | +828.1% |
| 1871 | 4.37 % change on previous year | -61.0% |
| 1872 | 10.62 % change on previous year | +143.2% |
| 1873 | 1.94 % change on previous year | -81.8% |
| 1874 | 3.96 % change on previous year | +104.6% |
| 1875 | 7.16 % change on previous year | +80.9% |
| 1876 | 7.3 % change on previous year | +1.9% |
| 1877 | 5.25 % change on previous year | -28.0% |
| 1878 | 1.97 % change on previous year | -62.6% |
| 1879 | 5.37 % change on previous year | +173.2% |
| 1880 | 8.32 % change on previous year | +54.9% |
| 1881 | 8.68 % change on previous year | +4.3% |
| 1882 | 5.32 % change on previous year | -38.7% |
| 1883 | 5.83 % change on previous year | +9.7% |
| 1884 | -0.4869 % change on previous year | -108.3% |
| 1885 | -0.0357 % change on previous year | -92.7% |
| 1886 | 4.07 % change on previous year | -11491.6% |
| 1887 | 1.88 % change on previous year | -53.8% |
| 1888 | 4.01 % change on previous year | +113.2% |
| 1889 | 8.6 % change on previous year | +114.4% |
| 1890 | 9.7 % change on previous year | +12.7% |
| 1891 | 6.72 % change on previous year | -30.7% |
| 1892 | 4.54 % change on previous year | -32.5% |
| 1893 | 1.13 % change on previous year | -75.0% |
| 1894 | 5.69 % change on previous year | +401.6% |
| 1895 | 1.39 % change on previous year | -75.5% |
| 1896 | 6.18 % change on previous year | +343.8% |
| 1897 | 3.24 % change on previous year | -47.5% |
| 1898 | 0.902 % change on previous year | -72.2% |
| 1899 | 4.63 % change on previous year | +413.7% |
| 1900 | 1.71 % change on previous year | -63.1% |
| 1901 | 2.21 % change on previous year | +29.2% |
| 1902 | 3.39 % change on previous year | +53.6% |
| 1903 | -1.32 % change on previous year | -138.9% |
| 1904 | 5.07 % change on previous year | -485.0% |
| 1905 | 2.54 % change on previous year | -50.0% |
| 1906 | 2.12 % change on previous year | -16.3% |
| 1907 | 1.46 % change on previous year | -31.2% |
| 1908 | 3.98 % change on previous year | +172.2% |
| 1909 | 1.55 % change on previous year | -61.0% |
| 1910 | 0.4425 % change on previous year | -71.5% |
| 1911 | -0.9401 % change on previous year | -312.5% |
| 1912 | 9.2 % change on previous year | -1079.1% |
| 1913 | 2.5 % change on previous year | -72.9% |
| 1914 | -4.71 % change on previous year | -288.4% |
| 1915 | -5.31 % change on previous year | +12.8% |
| 1916 | 8.29 % change on previous year | -256.2% |
| 1917 | -5.37 % change on previous year | -164.8% |
| 1918 | 3.34 % change on previous year | -162.1% |
| 1919 | -5.42 % change on previous year | -262.2% |
| 1920 | -4.53 % change on previous year | -16.3% |
| 1921 | 1.85 % change on previous year | -140.8% |
| 1922 | -1.31 % change on previous year | -170.7% |
| 1923 | 8.36 % change on previous year | -739.3% |
| 1924 | 3.45 % change on previous year | -58.8% |
| 1925 | 0.8791 % change on previous year | -74.5% |
| 1926 | -3.62 % change on previous year | -511.8% |
| 1927 | 12.45 % change on previous year | -443.9% |
| 1928 | -3.12 % change on previous year | -125.0% |
| 1929 | 10.62 % change on previous year | -441.0% |
| 1930 | -3.03 % change on previous year | -128.5% |
| 1931 | -1.8 % change on previous year | -40.6% |
| 1932 | -6.8 % change on previous year | +277.7% |
| 1933 | -9.85 % change on previous year | +44.9% |
| 1934 | 7.78 % change on previous year | -179.1% |
| 1935 | 7.59 % change on previous year | -2.4% |
| 1936 | -62.42 % change on previous year | -921.9% |
| 1937 | -30.17 % change on previous year | -51.7% |
| 1938 | 117.35 % change on previous year | -489.0% |
| 1939 | 10.76 % change on previous year | -90.8% |
| 1940 | 33.3 % change on previous year | +209.6% |
| 1941 | 0.9634 % change on previous year | -97.1% |
| 1942 | 6.58 % change on previous year | +582.6% |
| 1943 | 2.14 % change on previous year | -67.5% |
| 1944 | 6.59 % change on previous year | +208.5% |
| 1945 | 12.84 % change on previous year | +95.0% |
| 1946 | -2.83 % change on previous year | -122.0% |
| 1947 | 18.22 % change on previous year | -743.6% |
| 1948 | 3.47 % change on previous year | -81.0% |
| 1949 | 10.29 % change on previous year | +197.0% |
| 1950 | -8.49 % change on previous year | -182.5% |
| 1951 | 0.4582 % change on previous year | -105.4% |
| 1952 | 13.66 % change on previous year | +2881.5% |
| 1953 | 3.51 % change on previous year | -74.3% |
| 1954 | 2.44 % change on previous year | -30.3% |
| 1955 | 2.8 % change on previous year | +14.4% |
| 1956 | 8.77 % change on previous year | +213.8% |
| 1957 | 21.13 % change on previous year | +140.9% |
| 1958 | 10.88 % change on previous year | -48.5% |
| 1959 | -7.61 % change on previous year | -170.0% |
| 1960 | -2.43 % change on previous year | -68.1% |
| 1961 | 17.62 % change on previous year | -824.4% |
| 1962 | 9.26 % change on previous year | -47.5% |
| 1963 | -3.76 % change on previous year | -140.6% |
| 1964 | 19.78 % change on previous year | -626.1% |
| 1965 | 2.46 % change on previous year | -87.6% |
| 1966 | 12.52 % change on previous year | +408.8% |
| 1967 | 16.91 % change on previous year | +35.0% |
| 1968 | 17.41 % change on previous year | +3.0% |
| 1969 | 8.4 % change on previous year | -51.8% |
| 1970 | 9.48 % change on previous year | +12.8% |
| 1971 | 8.34 % change on previous year | -12.0% |
| 1972 | 2.93 % change on previous year | -64.9% |
| 1973 | 12.35 % change on previous year | +322.0% |
| 1974 | 16.88 % change on previous year | +36.7% |
| 1975 | 3.97 % change on previous year | -76.5% |
| 1976 | 18.3 % change on previous year | +360.5% |
| 1977 | -17.71 % change on previous year | -196.8% |
| 1978 | 2.15 % change on previous year | -112.2% |
| 1979 | 6.42 % change on previous year | +198.1% |
| 1980 | 16.92 % change on previous year | +163.6% |
| 1981 | 5.24 % change on previous year | -69.1% |
| 1982 | -8.85 % change on previous year | -269.0% |
| 1983 | -0.1058 % change on previous year | -98.8% |
| 1984 | -14.87 % change on previous year | +13948.5% |
| 1985 | -5.2 % change on previous year | -65.0% |
| 1986 | -1.97 % change on previous year | -62.2% |
| 1987 | -2.22 % change on previous year | +13.0% |
| 1988 | -9.01 % change on previous year | +305.8% |
| 1989 | 16.1 % change on previous year | -278.6% |
| 1990 | -0.7083 % change on previous year | -104.4% |
| 1991 | 1.54 % change on previous year | -316.7% |
| 1992 | -0.8516 % change on previous year | -155.5% |
| 1993 | -4.56 % change on previous year | +435.8% |
| 1994 | -2.89 % change on previous year | -36.7% |
| 1995 | -6.73 % change on previous year | +132.9% |
| 1996 | -7.45 % change on previous year | +10.7% |
| 1997 | 6.31 % change on previous year | -184.7% |
| 1998 | -4.71 % change on previous year | -174.6% |
| 1999 | 0.1916 % change on previous year | -104.1% |
| 2000 | -5.64 % change on previous year | -3045.5% |
| 2001 | -0.9166 % change on previous year | -83.8% |
| 2002 | 8.37 % change on previous year | -1012.9% |
| 2003 | -12.53 % change on previous year | -249.8% |
| 2004 | 2.91 % change on previous year | -123.2% |
| 2005 | -0.3454 % change on previous year | -111.9% |
| 2006 | -7.31 % change on previous year | +2016.3% |
| 2007 | -3.5 % change on previous year | -52.1% |
| 2008 | -45.56 % change on previous year | +1200.6% |
| 2009 | -13.06 % change on previous year | -71.3% |
| 2010 | -8.77 % change on previous year | -32.8% |
| 2011 | 9.71 % change on previous year | -210.7% |
| 2012 | -3.33 % change on previous year | -134.3% |
| 2013 | -20.34 % change on previous year | +510.1% |
| 2014 | 9.32 % change on previous year | -145.8% |
| 2015 | -3.52 % change on previous year | -137.8% |
| 2016 | -2.76 % change on previous year | -21.5% |
| 2017 | -2.62 % change on previous year | -5.2% |
| 2018 | -0.8053 % change on previous year | -69.3% |
| 2019 | -10.39 % change on previous year | +1190.7% |
| 2020 | -58.09 % change on previous year | +458.9% |
| 2021 | 8.24 % change on previous year | -114.2% |
| 2022 | 9.33 % change on previous year | +13.3% |
Spain compared with similar countries
- Spain's 9.33 % change on previous year is above the median for high income countries, which is 1.15 % change on previous year, 8.1× the median. (78 countries reporting)
- Spain's 9.33 % change on previous year is above the median for Europe & Central Asia, which is 0.9045 % change on previous year, 10.3× the median. (52 countries reporting)
Biggest year-on-year movements
Years where Sulphur dioxide and coal, annual growth rate in Spain changed far more than this series normally does. A large move can be a real event or a change in how the figure was measured — the source note below says who published it.
| Year | Change | From | To |
|---|---|---|---|
| 1984 | -13948.5% | -0.1058 % change on previous year | -14.87 % change on previous year |
| 1886 | +11491.6% | -0.0357 % change on previous year | 4.07 % change on previous year |
| 2000 | -3045.5% | 0.1916 % change on previous year | -5.64 % change on previous year |
| 1952 | +2881.5% | 0.4582 % change on previous year | 13.66 % change on previous year |
| 2006 | -2016.3% | -0.3454 % change on previous year | -7.31 % change on previous year |
| 2008 | -1200.6% | -3.5 % change on previous year | -45.56 % change on previous year |
Averages by decade
| Decade | Average | Lowest | Highest | Years |
|---|---|---|---|---|
| 1750s | 0.1003 % change on previous year | 0.0961 % change on previous year | 0.1044 % change on previous year | 9 |
| 1760s | 0.097 % change on previous year | 0.093 % change on previous year | 0.1014 % change on previous year | 10 |
| 1770s | 0.0939 % change on previous year | 0.0899 % change on previous year | 0.0985 % change on previous year | 10 |
| 1780s | 0.0905 % change on previous year | 0.0866 % change on previous year | 0.0951 % change on previous year | 10 |
| 1790s | 0.0871 % change on previous year | 0.083 % change on previous year | 0.0917 % change on previous year | 10 |
| 1800s | 0.0835 % change on previous year | 0.0792 % change on previous year | 0.0882 % change on previous year | 10 |
| 1810s | 0.0799 % change on previous year | 0.0755 % change on previous year | 0.0847 % change on previous year | 10 |
| 1820s | 0.4297 % change on previous year | 0.0743 % change on previous year | 0.4889 % change on previous year | 10 |
| 1830s | 5.85 % change on previous year | 1.54 % change on previous year | 9.02 % change on previous year | 10 |
| 1840s | 7.17 % change on previous year | 0.8687 % change on previous year | 16.1 % change on previous year | 10 |
| 1850s | 9.02 % change on previous year | -3.8 % change on previous year | 20.75 % change on previous year | 10 |
| 1860s | 3.74 % change on previous year | -2.3 % change on previous year | 10.8 % change on previous year | 10 |
| 1870s | 5.91 % change on previous year | 1.94 % change on previous year | 11.2 % change on previous year | 10 |
| 1880s | 4.62 % change on previous year | -0.4869 % change on previous year | 8.68 % change on previous year | 10 |
| 1890s | 4.41 % change on previous year | 0.902 % change on previous year | 9.7 % change on previous year | 10 |
| 1900s | 2.27 % change on previous year | -1.32 % change on previous year | 5.07 % change on previous year | 10 |
| 1910s | 0.2031 % change on previous year | -5.42 % change on previous year | 9.2 % change on previous year | 10 |
| 1920s | 2.5 % change on previous year | -4.53 % change on previous year | 12.45 % change on previous year | 10 |
| 1930s | 2.94 % change on previous year | -62.42 % change on previous year | 117.35 % change on previous year | 10 |
| 1940s | 9.16 % change on previous year | -2.83 % change on previous year | 33.3 % change on previous year | 10 |
| 1950s | 4.75 % change on previous year | -8.49 % change on previous year | 21.13 % change on previous year | 10 |
| 1960s | 9.82 % change on previous year | -3.76 % change on previous year | 19.78 % change on previous year | 10 |
| 1970s | 6.31 % change on previous year | -17.71 % change on previous year | 18.3 % change on previous year | 10 |
| 1980s | -0.397 % change on previous year | -14.87 % change on previous year | 16.92 % change on previous year | 10 |
| 1990s | -1.99 % change on previous year | -7.45 % change on previous year | 6.31 % change on previous year | 10 |
| 2000s | -7.76 % change on previous year | -45.56 % change on previous year | 8.37 % change on previous year | 10 |
| 2010s | -3.35 % change on previous year | -20.34 % change on previous year | 9.71 % change on previous year | 10 |
| 2020s | -13.51 % change on previous year | -58.09 % change on previous year | 9.33 % change on previous year | 3 |
Countries ranked near Spain
- 48 Burundi 10.57 % change on previous year compare
- 49 Benin 9.88 % change on previous year compare
- 50 Congo 9.49 % change on previous year compare
- 52 Singapore 9.26 % change on previous year compare
- 53 Sweden 9.12 % change on previous year compare
- 54 Switzerland 9.1 % change on previous year compare
More energy & mining data for Spain
- Fossil fuel consumption by fuel, per capita 0 terawatt-hours per person (2025)
- Fossil fuel consumption by fuel, per unit of GDP 0 terawatt-hours per US$ of GDP (2025)
- Primary energy use, annual growth rate 2.17 % change on previous year (2025)
- Coal consumption, per capita 0 terawatt-hours per person (2025)
- Coal consumption, per unit of GDP 0 terawatt-hours per US$ of GDP (2025)
- Primary energy use, per unit of GDP 0 terawatt-hours per US$ of GDP (2025)
- Primary energy use, per capita 0 terawatt-hours per person (2025)
- Coal production, per capita 0 terawatt-hours per person (2025)
- Coal production, per unit of GDP 0 terawatt-hours per US$ of GDP (2025)
- Fuel imports 13.4% (2024)
Frequently asked questions
- What is sulphur dioxide and coal, annual growth rate in Spain?
- Sulphur dioxide and coal, annual growth rate in Spain was 9.33 % change on previous year in 2022, according to Statizoid (derived).
- What is the highest sulphur dioxide and coal, annual growth rate recorded in Spain?
- The highest recorded value was 117.35 % change on previous year in 1938.
- What is the lowest sulphur dioxide and coal, annual growth rate recorded in Spain?
- The lowest recorded value was -62.42 % change on previous year in 1936.
- How does Spain rank for sulphur dioxide and coal, annual growth rate?
- Spain ranks 51st out of 219 countries with data for 2022.
- Is sulphur dioxide and coal, annual growth rate rising or falling in Spain?
- Over the last ten years it is up 379.9%. The long-run trend across the full record is volatile.
- Where does this Spain data come from?
- The figures come from Statizoid (derived), published as part of Sulphur dioxide and coal, annual growth rate. Statizoid updates them automatically from the source API.
Download this data
CSV · JSON — 272 observations, free to reuse under Derived by Statizoid from the sources named on the page.
How this figure is calculated
The year-on-year percentage change in Sulphur dioxide and coal. Computed from consecutive annual observations; years either side of a gap are skipped rather than bridged.
Computed from
- Coal consumption and sulphur dioxide emissions Hoesly et al. (2024) – Community Emissions Data System (CEDS) – with major processing by Our World in Data
Statizoid computes this series; the underlying measurements belong to the publishers named above. The arithmetic is applied to every country and year where both inputs report, and nothing is estimated unless the page says so.
About this data
The year-on-year percentage change in Sulphur dioxide and coal. Computed from consecutive annual observations; years either side of a gap are skipped rather than bridged.