How many vegetarians and vegans are there?:

Vasile’s Substack on this topic

And an earlier guest blog post Vasile wrote about the same issue

Pew 2016 - 9%

Gallup 2018 - 8% (deceptively saying 5% vegetarian and 3% vegan with the headline describing the number as “few”. Many interpret this to mean that the 3% is part of the 5% (since vegans are necessarily also vegetarian), but it is actually additive. Also note higher numbers in younger age groups

Vegetarian Resource Group - How Many Vegetarians and Vegans are There?

What are the lowball figures?

Faunalytics - You can see that they do show growing numbers, but much lower than other sources. This info leads them to recommend less radical tactics, such as “Encourage Change In Many Forms” ie. reducing meat rather than becoming vegan.

Defaulting to vegan meals:

Science Direct