In Corporate Communications, there are few things more awful than the 'boasting (quite possibly lying) about the amazing successes of the last year' blog post. 

But this review of 2019 blog from Stephenson Law, a small firm in Bristol, is fantastic. I would still recommend that you do not write the 'looking back' post but if you must, then do it like this. 

Self-deprecating, witty, short and with humanity - but they still made their point. We are here and we are good at this.

"Laura had her 1 year work anniversary and we bought her a balloon."