diff --git a/single_file_tests/time.rs b/single_file_tests/time.rs
index 71b635a..d089a07 100644
--- a/single_file_tests/time.rs
+++ b/single_file_tests/time.rs
@@ -4,7 +4,7 @@ fn get_year_and_left_secs(secs_from_1970: u64) -> (u32, u64) {
     let mut t = secs_from_1970;
     let mut y = 1970;
     loop {
-        let is_leap_year = y % 4 == 0 && y % 100 != 0;
+        let is_leap_year = (y % 4 == 0 && y % 100 != 0) || (y % 400 == 0);
         let secs_per_year = if is_leap_year { 366 } else { 365 } * 24 * 60 * 60;
         if t > secs_per_year {
             y += 1;
@@ -23,4 +23,4 @@ fn main() {
     println!("Secs from 1970: {}", secs_from_1970);
     println!("Year (GMT)    : {}", year_gmt);
     println!("Year (GMT+8)  : {}", year_gmt8);
-}
\ No newline at end of file
+}