Focusing on a different potential explanation, Ghayad and William Dickens performed a separate analysis of the U.S. labor market to examine whether a skill gap was to blame for the current high rate of long-term unemployment, and concluded that a skills gap was largely not to blame for the recent inefficiencies in the U.S. labor market as seen in the Beveridge curve since 2009.14 Their analysis looked at the differences between the Beveridge curves for different types of workers in order to determine if it was likely that a skills gap was causing the shift seen in the Beveridge curve for all workers. A similar shift happened in the 1970s, and this, it is believed, was a result of a gap between the skills of workers and the ones being sought by employers. In the case of the 1970s, the shift happened for both long and short term employed workers, and mostly affected blue-collar workers. The Beveridge curve today, though, is similar for blue and white collar workers, across several industries, and across different age groups. However, while there is an evident shift in the curve for workers who have been unemployed for 27 weeks or more, unemployed workers of shorter durations have experienced no outward shift in the Beveridge curve. They conclude that being unemployed for a longer amount of time has an effect on the chances that a worker will become employed, suggesting that being long-term unemployed is in itself a cause of the persistence in unemployment.