Firstly lets make this very clear the Czech Republic only came into existence in 1993 following the collapse of the U.S.S.R.
So accuracy means the Czech Republic can only celebrate 25 years
Czechoslovakia was created from the remnants of the Austro-Hungarian empire in 1918 but that only lasted until 1938 following the german invasion of the sudetenland which became Bohemia and Moravia until 1945 following the liberation by the Allies, the Czechoslovakia was reborn until it's dissolution in 1993.
So ;_
Czechoslovakia lasted for 68 years
Bohemia and Moravia lasted for 7 years
The Czech Republic and Slovak Republic so far only 25 years
I wish World of Tanks would correct the title to 25 years