A year starts on Jan 1. The first day of the week is determined by the
locale.
.PP
-The week numbering depends on the first day of the week. If Sunday (the
-default) is used for the first day of the week, then the customary North
-American numbering will be used, i.e. first Sunday of the week starts the
-first week. If Monday is selected, then the ISO-8601 standard week numbering
-is used, where the first Thursday is in week number 1.
+The week numbering depends on the choice of the first day of the week. If Sunday
+(the default) is used for the first day of the week, then the customary North
+American numbering will be used, i.e. the first Sunday of the year starts the
+first week. If Monday is selected, then the ISO-8601 standard week numbering
+is used, where the first Thursday of the year is in week number 1.
.SH BUGS
.PP
The