See here. The graph for six month active users is a little glitchy (I think because lemmy.ml was listed twice under two different URL).
There does seem to be very small growth in 6 month active users, not as fast as a few other fediverse platforms (such as friendica and writefreely) . but i got my fingers crossed that third party lemmy tools will create some really compelling features and help push the adoption of lemmy (I think addons can enhance open source software, like how firefox addons helped firefox adoptions).