Article: At the end of the 1980s, Estonians perceived their demographic change as a national catastrophe. This was a result of the migration policies essential to the Soviet Nationalisation Programme aiming to russify Estonia – administrative and military immigration of non-Estonians from the USSR coupled with the deportation of Estonians to the USSR. In the decade following the reconstitution of independence, large-scale emigration by ethnic Russians and the removal of the Russian military bases in 1994 caused the proportion of ethnic Estonians in Estonia to increase from 61% to 69% in 2006.

Now answer this question: How did Estonians view the demographic change of less ethnic Estonians?
a national catastrophe