With (two months after) vs without = ~0.2 vs 0.05×0.5×0.2 = ~20% vs ~0.5%

(Explanation: chance of symptomatic disease 2 months after reported as 5% vs "control"; chance of long COVID after symptomatic infection reported as 2.3% as bare minimum, 13% to other research and 40% to a large interpretation.)

Edit: to the three British studies of 2.3%, 13% and 40%, after this thread I can add 25% from a post from user tfehring, including link to article: «something like a quarter of people with symptomatic COVID seem to have some kind of cognitive symptom (mainly “brain fog” and/or short-term memory loss) 8 months later». I will update the tentative value for the chance of long COVID, but the ratio, half of one twentieth, does not change.