The English language proficiency of immigrants has increased, most notably in the past ten or so years. This upward trend is seen in important groups such as Mexicans. But English language proficiency of Mexican immigrants declined in the 1990s. What was the impact of that, and why did it happen? The explanation has to do with demographics of immigrants and job growth in the 1990s.
Researchers looked at the impact on earnings and education when immigrants learn English. English proficiency helps in getting better paying jobs. It also enables the immigrant to obtain more formal education. Another study found that the benefits of English proficiency were primarily in becoming more educated. Young persons with English were more inclined to complete high school.
Demographic trends actually caused English proficiency among low skilled immigrants to decline. In 1990, 80% of individuals from non English-speaking countries said that they spoke English very well. In 2000, 70% said so. The decline is due to the large increase in immigrants, many unauthorized, in the 1990s.
During that decade, an hourglass profile of workers and jobs enlarged. There was a sharp increase in demand for service workers such as food preparation, janitors, gardeners, security guards, housekeeping ,cleaning and laundry workers. These low skilled jobs require limited language skills.
The English language skills of these jobholders declined in the 1990s. On factor in lower English proficiency is that with larger numbers of non-English proficient residents, these individuals were more able to find work that did not require English proficiency. This led to great linguistic and cultural isolation.
One researcher, writing in 2015 (Cassidy) found a large decline in the earnings of childhood immigrants in the U.S. between 1990 and 2010, and in particular during the 1990s. This drop in earnings has occurred across all age at arrival groups, but has disproportionately impacted lower-educated immigrants. A large decline in English language proficiency can explain much of this trend. A concentration of source countries (largely, through not entirely, due to an increase in Mexican immigration) has also contributed, mainly through the negative impacts it has had on English language proficiency and education levels.
See: Language Skills and the Earnings Distribution Among Child Immigrants, by Wang and Wang
The Decline in Earnings of Childhood Immigrants in the U.S., by Cassidy