In the entire Canton of Grisons, where about two-thirds of all speakers live, roughly a sixth report it as the language of best command (29,679 in 1990 and 27,038 in 2000). As a family language it was used by 19.5% in 2000 (33,707), as a language used on the job by 17.3% (15,715), and as a school language by 23.3% (5,940). Overall, 21.5% (40,168) of the population of Grisons reported to be speaking Romansh habitually in 2000. Within the traditional Romansh-speaking areas, where 56.1% (33,991) of all speakers lived in 2000, it is the majority language in 66 municipalities.
Question: How many years did it take for 2641 less people to regard it language of best command?
Answer: 10