Short answers, pulled from the story.
The Soviet Union began a radical transformation of its economic life in 1928. The state seized control of all means of production and replaced market mechanisms with an administrative-command system.
GDP levels in 1950 reached 510 billion 1990 dollars, surpassing Japan's 161 billion but remaining far below the United States' 1,456 billion. This figure reflects the industrial output achieved after the first five-year plan took effect in 1930 under Joseph Stalin's close supervision.
Estimates suggest between 5.7 and 8.7 million people died due to collectivization policies during the mass famine known as the Holodomor. Millions of Ukrainians starved when collective farms known as kolkhozes replaced private peasant holdings across the countryside.
World oil prices collapsed in 1986 after quadrupling in the 1973, 1974 period and rising again in 1979, 1981. The vast supplies of oil and gas covered multiple weaknesses until this price drop occurred.
The value of all consumer goods manufactured in 1990 was about 459 billion roubles or $2.1 trillion. This figure represents the economic output before the dissolution at the end of 1991 when the successor state inherited a growing pile of $66 billion in external debt.