The fillér denomination was still relatively new in 1900. They created the denomination in 1892 when they adopted the gold standard. So, you see a lot of 1, 2, 10, and 20 fillér coins struck in those first years as they were intended to replace the older coinage. Take a look at the mintage numbers for the 1 and 2 fillér for 1892-1901: 1 fillér 1892 - 8,153,000 1893 - 8,152,507 1894 - 8,641,784 1895 - 9,121,315 1896 - 5,396,972 1897 - 5,156,580 1898 - 1,419,348 1899 - 5,065,895 1900 - 10,461,111 1901 - 5,993,930 2 fillér 1892 ? 1893 - 17,176,179 1894 - 39,150,321 1895 - 65,016,511 1896 - 53,715,725 1897 - 37,296,844 1898 - 14,972,860 1899 - 21,569,648 1900 - 584,449 1901 - 25,805,472 You can see they struck way more of the 2 fillér overall, but the relatively small mintage of 1900 coincides with a surge of production for the 1 fillér the same year. Both coins had planchets stamped from ~1mm thickness bronze. I'm guessing they just thought they needed more of the 1 fillér that year? Interestingly, during the forint period (1867-1892), they revised the coinage every decade, starting with 1870. They did not do this in 1900 (I suppose since all the coinage was redesigned in 1892?).
