Use decimals and commas for English figures as follows:

General Figures: 22,500 people, 1.5 million cars, 42.8 square meters

Money figures: $4,564.54, $4.5 million, 5.67 billion Turkish lira

Percents: 43.8 percent (in writing), 43.8% (in numbers)

Note: Decimals and commas in Turkish figures are reversed. When translating, you need to be careful in correcting the numbers and aligning them with proper English format.

 

Source
Dragoman Style Guide for Figures