This is an applied econometric analysis of labour market data for the United States. We study the impact of several factors on overflow of overeducated employees into various job categories. We use panel data regression analysis with fixed and random effects. We also use data visualisation to investigate the overeducation trends during 2002-2016 for various occupation categories. Our dataset consists of seven sets of annual data for 704 occupations. We investigate this phenomenon at two levels: 1) overflow of university graduates into occupations that do not require a university degree, and 2) overflow of Masters and PhD degree holders into occupations that require a bachelor's degree or less. We observe that the overeducation has increased in most occupations and it causes a crowding out effect; an adequately educated worker might be outcompeted by an overeducated worker. While the income premium of a university education has decreased over time, the income advantage of university education over a high school degree has persisted. Furthermore, our regression analysis has shown that the overeducation ratio has a positive correlation with the median earnings of an occupation and its opportunities for self-employment. The results hold for both college graduates and holders of graduate degrees.