Your itemized deductions for state and local taxes include:
- Real Estate Taxes
- Personal Property Taxes (ex. car tax)
- State Income Taxes
Most likely, your state withholdings on your W-2(s) and real estate taxes from your 1098 mortgage statement maxed out the $10,000 limit.
Last year's tax reform introduced a new $10k limit on these deductions. In years 2017 and earlier, you were not capped.