+The @subcmd{N} subcommand may be used to specify the number
+of valid cases for each variable. It should not be used if the
+data contains a record whose ROWTYPE_ column is @samp{N} or @samp{N_VECTOR}.
+It implies a @samp{N} record whose values are all @var{n}.
+That is to say,
+@example
+matrix data
+ variables = rowtype_ var01 TO var04
+ /format = upper nodiagonal
+ /n = 99.
+begin data
+mean 34 35 36 37
+sd 22 11 55 66
+corr 9 8 7
+corr 6 5
+corr 4
+end data.
+@end example
+produces an effect identical to
+@example
+matrix data
+ variables = rowtype_ var01 TO var04
+ /format = upper nodiagonal
+begin data
+n 99 99 99 99
+mean 34 35 36 37
+sd 22 11 55 66
+corr 9 8 7
+corr 6 5
+corr 4
+end data.
+@end example
+
+