State tax filing

I believe New Mexico switched from 5% to 4.875 mid year so I assume the 4.94 rate is an average of the two.

I believe the program gets this rate from the IRS. 

This is the rate the program uses for "Easy Guide" input, were the sales tax is based on your income.

You can use "Easy Guide" and also enter large purchase items.

For specific items, you enter the total (State plus Local) sales tax.

This total state and local tax rate is entered by you.

The final deduction is the tax calculated on your income as well as the tax paid on large purchases. 

For major purchases, the tax paid will only be counted on Vehicles (cars, trucks, motorcycles, off-road vehicles) 

AND other items that paid the same tax rate as what you entered as State plus Local. These items include:

Boats

Planes

Mobile Homes

Manufactured Homes

Home Improvement Material 

(NOTE: if the tax rate you enter for these other items is not exactly the same as what you entered as the state and local tax rate, the tax paid will not be added)

State and Local tax deductible on Schedule A is limited to 10,000 no matter what you paid. 

In Step-by-Step I went to 

Deductions & Credits 

Estimates and Other Taxes Paid

Sales Tax     START or UPDATE

Once I entered information in this section it was difficult (although not impossible) to edit.

If you want to start over and since you are working with Desktop, you might switch to FORMS and Delete 

Tax & Int Wks

@OhTheQuestions