Nuheara max sales

Over the past couple of months I've started to try and track sales of max.
it's obviously a very difficult process to do. The only metric that I can use that is available publicly would be to use the number of reviews as an indication of sales. Obviously more reviews would mean an increase in sales but it won't tell us how many sales. I tried to formulate that but was unable to get any accuracy.
what I can say is that review numbers have hardly grown over the past month.
currently review numbers
Nuheara 825 (had 819 early Jan)
Amazon 23 (from early December they had 0)
walgreens 21 (most recent was 4 months ago)
walmart 0 reviews!
best buys 6 reviews (most recent 2 weeks ago)
Hear for less 0 reviews
sonova australia - have no reviews on website
sonova USA - not on website
product review .com - 14 reviews most recent 5 months ago

it seems pretty clear that sales have slowed ....