Years earlier than what is shown here are under Archived Years - click the little triangle under Newsletters. The older newsletters are zipped into a folder at the link for each year. To access the files in that folder you must download the folder and unzip it. The all months on record for that year will be available.
On this page, blue indicates the newsletter exists and the month name is a link to download the file for that month. If the month is black, there is no link because there was no newsletter published.