Short answer
Slowly, except around elections. The typical page grew by about half a per cent a month, and growth was several times faster in the months around national elections.
What the evidence shows
- The study tracks the page likes of 112 party pages and 74 leaders' pages in 20 European countries month by month from 2016 to 2020. Growth slowed from about 1.3% a month in 2016 to about 0.3% from 2018.
- Compared with the same page in other months, pages grew by about 3 log points more in the month before a national election and about 5 more in the month of the election, but no faster in the month after.
- The month before and the month of an election made up 5% of page-months and 18% of growth.
- Pages gained more followers in months when they received more engagement; posting more without more engagement went with no extra growth. A change of party leader did not add followers.
Caveats
Most cumulative growth still accrued, slowly, in ordinary months.