income tax credit and when you look across the united states you do see some relationships between areas that have different measures of tax expenditures like higher property tax rates and greater amounts of income tax credit. but really we found four factor where s the strongest correlates with upward mobility. the four were the quality of the k-12 education system, the degree of incomes in inequality and segregation, the strength of social ties and the amount of civic engagement, finally, the strength of the family structure. so various nae sure of the strength of family. good schools, strong fam ii y families, full households seem to be the strongest correlaters. that s right. that s right. give you an example. you measure the family structure. in areas where there s a higher fraction of people born to single mothers, lower rates of upward mobility. one thing to mention on that that holds true not only to people born to single mothers but those born to married parents as well. i