One economic success of the 1970s was the development of Soviet oil fields. While doubtless "(Central and) East Europeans resented having to defray some of the costs of developing the economy of their hated overlord and oppressor," they benefited from low prices for fuel and other mineral products. As a result, Comecon economies generally showed strong growth in the mid-1970s. They were largely unaffected by the 1973 oil crisis. Another short-term economic gain in this period was that "détente" brought opportunities for investment and technology transfers from the West. This also led to an importation of Western cultural attitudes, especially in Central Europe. However, many undertakings based on Western technology were less than successful (for example, Poland's Ursus tractor factory did not do well with technology licensed from Massey Ferguson); other investment was wasted on luxuries for the party elite, and most Comecon countries ended up indebted to the West when capital flows died out as "détente" faded in the late 1970s, and from 1979 to 1983, all of Comecon experienced a recession from which (with the possible exceptions of East Germany and Bulgaria) they never recovered in the Communist era. Romania and Poland experienced major declines in the standard of living.