y is the "ordinate".
See also:
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... 1850s 1860s 1870s 1880s 1890s - 1900s - 1910s 1920s 1930s 1940s 1950s Years: 1899 1900 1901 1902 1903 - 1904 - 1905 1906 1907 1908 1909 See ...