Does anyone how Lacerte calculates the real estate taxes which are being carried to Line 5 of From 4952?  On Sch A I entered $90,100 in real estate taxes on the property held for investment line and $9,857 on the principal residence line. Lacerte calculates a sales tax deduction of $2,177 (total taxes are $102,134). Of course the entire deduction is being limited to the $10,000, but $8,822 is automatically carrying to Line 5 of Form 4952.  Why $8,822?  I've attached a screen shot of the worksheet for Line 5.