-# since 1900.0 and the second column shows the number of
-# seconds that must be added to UTC to compute TAI for
-# any timestamp at or after that epoch. The value on
-# each line is valid from the indicated initial instant
-# until the epoch given on the next one or indefinitely
-# into the future if there is no next line.
+# since 1 January 1900, 00:00:00 (1900.0 is also used to
+# indicate the same epoch.) Both of these time stamp formats
+# ignore the complexities of the time scales that were
+# used before the current definition of UTC at the start
+# of 1972. (See note 3 below.)
+# The second column shows the number of seconds that
+# must be added to UTC to compute TAI for any timestamp
+# at or after that epoch. The value on each line is
+# valid from the indicated initial instant until the
+# epoch given on the next one or indefinitely into the
+# future if there is no next line.