1855 was the last year of the With Arrows type, apparently because there were sufficient quantities of the new, lighter-weight Dimes in circulation by then. Between 1853 and 1855, the Philadelphia and New Orleans Mint struck over 21 million With Arrows Dimes, an unprecedented quantity meant to drive the old Dimes from circulation. Philadelphia was the only mint to produce Dimes in 1855; the New Orleans Mint employees were granted a reprieve from such duties until the next year.
In terms of original mintages, survival rates, and numbers of Mint State examples, the 1854-O and 1855 Dimes mimic each other closely. Their populations in all grades at PCGS are nearly identical. Like the 1854-O Dime, the 1855 is seen most frequently in MS63 and MS64. The one difference between the two is that there are several PCGS-graded MS67 1855 Dimes atop the Census, plus there is an NGC MS68 ranked as finest known.