I can't find historical data for MCPS. But for Montgomery County overall, the Census says that in 2012, 14.7% of the Montgomery County population was Asian (total population 1,004,709). (MCPS currently classifies 14.3% of students as Asian.) In 2010, it was 13.9% (total population 971,777). In 2000, it was 11.3% (total population 873,341).

Montgomery County is not losing its Asian population.