A study on Germany found that foreign-born parents are more likely to integrate if their children are entitled to German citizenship at birth. A 2017 study found that "faster access to citizenship improves the economic situation of immigrant women, especially their labour market attachment with higher employment rates, longer working hours and more stable jobs. Immigrants also invest more in host country-specific skills like language and vocational training. Faster access to citizenship seems a powerful policy instrument to boost economic integration in countries with traditionally restrictive citizenship policies." Naturalization is associated with large and persistent wage gains for the naturalized citizens in most countries. One study of Denmark found that providing immigrants with voting rights reduced their crime rate.