Lets assume 97.0000% of these are correct, thats 1843 correct and 57 not. In order to reach 97.5% (I assume thats when 98% will be shown) he would have to make 2223 total correct reports vs 57 bad. Thats 380 good reports without fail.
Accuracy is always rounded down IIRC, so it'll take even longer.
People shouldn't worry about accuracy much, and certainly not single percentage points.
In that case its just 950 correct reports

-snip-
Thanks, I wanted to add the actual math to show just how far the spread can be but ...I''m bad at math (it's why I changed my major from comp sci).
I actually just made a spreadsheet, maybe thats why I dropped out of math as a major

