As you can see the graph shows you the average number of Vietnamese students studying in France, Russia and America between 2000 and 2015. Between 2000 and 2010 the number of Vietnamese students studied in France and Russia decreased sharply. From 3. 5 million students in France in 2000 to 2. 5 million students in 2010. And dropped from 3 million to 1. 9 million students in Russia. After that, the number of Vietnamese students in both countries raised to 4. 5 million for France and 2. 5 million for Russia. But the number of Vietnamese students in the US has always increased steadily over the years. It raised from 1. 5 million to 5 million in 15 years. The reason for that disparity, I think is because Vietnamese students though that America is the best place for their to live and study and they can make a lot of money after they complete their education. 
As you can  
see
 the graph  
shows
 you the average  
number
 of Vietnamese  
students
 studying in France, Russia and America between 2000 and 2015. Between 2000 and 2010 the  
number
 of Vietnamese  
students
 studied in France and Russia decreased  
sharply
. From 3. 5  
million
  students
 in France in 2000 to 2. 5  
million
  students
 in 2010. And dropped from 3  
million
 to 1. 9  
million
  students
 in Russia. After that, the  
number
 of Vietnamese  
students
 in both countries raised to 4. 5  
million
 for France and 2. 5  
million
 for Russia.  
But
 the  
number
 of Vietnamese  
students
 in the US has always increased  
steadily
 over the years. It raised from 1. 5  
million
 to 5  
million
 in 15 years. The reason for that disparity, I  
think
 is  
because
 Vietnamese  
students
 though that America is the best place for their to  
live
 and  
study and
 they can  
make
  a lot of
 money after they complete their education.