人数は減るとは思うけど、そんなに多くないと思うって英語でなんて言うの？

人数 - number of people 減る - go down, decrease 人数が減る - number of people go down, number of people decrease 〜〜と思う - I think そんなに多くない - not that big, not that much I think the number of people will decrease, but I dont think it’ll be that much I think the amount of people will go down, but not by much