Bigger Pockets Calculator... Understanding their calculations

[James M.]

Hey everyone, so I need a little assistance understanding how BP's calculator is crunching their number on NOI. While trying to further enhance my analysis, I was running my own analysis compared to BP'S and I am having trouble understanding how they are getting this NOI. I will list some numbers below.

Gross Annual Rents: 60,600

P&I: 2881. 20

PMI: 100

Monthly Expenses

Vacancy: 252.20

Cap Ex: 252.20

Misc: 150

Repairs: 101

Water/sewer: 100

Insurance: 87

Property Tax: 740

Total: 1682/mo

Here is how I've calculated NOI:

Annual Gross Income - Annual Expenses = NOI

60,600 - (1682x12) = 40,416

The BP calculator is showing an NOI of 39,204.00.

With that being said, what the heck am i calculating incorrectly??