README.rdoc in writeexcel-0.6.12 vs README.rdoc in writeexcel-0.6.13

@@ -74,9 +74,15 @@
 
 You must save source file in UTF8 and run ruby with -Ku option or set $KCODE='u'
 when use urf8 string data.
 
 == Recent Changes
+v0.6.13
+* Bug fix issue 19. Workbook#store_num_format, format written in utf8 raise exception.
+
+v0.6.12
+* Bug fix issue 17. Worksheet#store_formula shouldn't be private
+
 v0.6.11
 * Bug fix issue 15. Worksheet#write_comment on the same row overwrite other comments.
 
 v0.6.10
 * Bug fix. method missing split_string_setup() in shared_string_table.rb. see https://github.com/cxn03651/writeexcel/pull/13