The Cepheid variable IY
Cygni was studied, and its O-C curve was found to be a straight line when
compared to the original elements found by A. A. Wachmann. The new elements are
JD(max) = 244005.769(+/-0.056) + 21.75661(+/-0.00070) E. Possible change over time
in the mean light curve are indicated.