Citizen Promaster Sky Super Skyhawk JY0080-62E Instruction Manual page 30

Month and year indications
The year and month are indicated by the chronograph second hand.
Nov.
Oct.
Sep.
Aug.
Jul.
Jun.
The position of the chronograph second hand
shows the month.
28
Dec.
Jan.
Feb.
Mar.
Apr.
May
e.g. When it is March in the leap year
Each minute mark denotes the number of years
since a leap year.
Leap year
1st year since leap year
2nd year since leap
year
3rd year since leap
year