Complex sentence: A particularly strong performance in agriculture was recorded in 1976--up more than 10 percent from 1975--but production dropped back to approximately 95 percent of the 1976 level in 1977 and 1978 and recovered to a level higher than that of 1976 only in 1979.
Split into simpler sentences: A particularly strong performance in agriculture was recorded in 1976--up more than 10 percent from 1975. However, production dropped back to approximately 95 percent of the 1976 level in 1977 and 1978 and recovered to a level higher than that of 1976 only in 1979.