What decimal point round off mileage

[SurePatience]

My percentage of mileage for business was 89.977318% of my total kilometres. What decimal point should I round it off to?  Should it be 90%? 89.98? 

[TurboTaxSusan]

TurboTax is going to ask you how many total kilometres you drove in the year, and how many kilometres you drove for business/work, and then calculate the percentage for you.