national strength; state of a country
Refers to a country's overall condition, especially its population, economic power, and resources. Often used in compound terms like 国勢調査 (national census).
The national census is conducted every five years.
That policy is meant to halt the decline of the nation's strength.
国政 (national government/administration) is a homophone of 国勢 (national strength/condition) but refers to governing affairs, not statistical national strength.
国勢 and 国情 share the kanji 国 and look similar, but 国勢 focuses on national power or population statistics, while 国情 covers the broader political and social situation.
national census; census
Compound of 国 (country) and 勢 (power, force, energy). The term has been used since the Meiji era to describe national conditions, especially in statistical contexts.