diff --git a/countleaps.m b/countleaps.m
index 2f1f2c9d9c4d08a715ce931a0501963d2d0ce9b1..c79d88a61b1b423d5231f0c1df184dfad3adddeb 100644
--- a/countleaps.m
+++ b/countleaps.m
@@ -1,3 +1,3 @@
 function leaps = countleaps(year)
 % calculates number of leapyears since 1 AD
-leaps = floor((year-1)/4) - floor((year-1)/100) + floor((year-1)/400);
+leaps = floor((year-1)/4) - floor((year-1)/100) + floor((year-1)/400) + 1;