How backlogs are counted in the USA?

Hey, You can have up to 15 backlogs to get admitted into US universities but not more than that.

Here is a list of FACTORS affecting the backlogs in the USA - 

1. Overall GPA / CGPA
One of the most important considerations during your admission is academic GPA along with/ or CGPA. This is even more important when you are seeking admission with backlogs. Having a very low GPA with backlogs can make your chances of admission bleak. 

2. Repeated Backlogs
Repeated Backlogs refer to the time taken or the number of attempts taken to clear the backlogs. Time plays a significant role. If you have a larger number of repeated attempts of a single backlog, the chances that you will get rejected are higher.

3. Backlog Status
Most of the universities in the USA do not accept admission if they have active backlogs. The number of attempts to complete a backlog, active backlogs, and inactive backlogs is in a Backlog Certificate, which is mandatory to submit for every student. 

LIST OF UNIVERSITIES ACCEPTING BACKLOGS -

Kent State University, Ohio
Wright State University, Ohio
Wichita State University, Kansas
Gannon University, Pennsylvania
Clarkson University, New York
Marist College, New York New York Institute of Technology (NYIT), Old Westbury
California State University, San Bernardino
University of South Dakota, Vermillion
Clark University, Massachusetts
Illinois Institute of Technology (IIT), Chicago

I hope this helps.