Dining in restaurants has become increasingly popular, with the proportion of meals consumed outside the home in restaurants or institutions rising from 25% in 1950 to 46% in 1990. This is caused by factors such as the growing numbers of older people, who are often unable or unwilling to cook their meals at home and the growing number of single-parent households. It is also caused by the convenience that restaurants can afford people; the growth of restaurant popularity is also correlated with the growing length of the work day in the US, as well as the growing number of single parent households. Eating in restaurants has also become more popular with the growth of higher income households. At the same time, less expensive establishments such as fast food establishments can be quite inexpensive, making restaurant eating accessible to many.