Many factors contribute to the gender pay gap in the US. Differences in salaries can be explained by occupational segregation (there are more women in lower-paid industries and more men in higher-paid industries) and vertical segregation (there are fewer women in senior and executive - better paying - positions). Other factors contributing to wage differences between genders include women’s overall paid working hours, the inability to enter into the labor market due to barriers such as single parenting rate and education level, and ineffective equal pay legislation.