Complex sentence: Sales increased annually and peaked in 1973, when 14,500 cars were sold through a 268-dealer network, but collapsed to 3462 in 1973 and 344 in 1975.
Split into simpler sentences: Sales increased annually and peaked in 1973, when 14,500 cars were sold through a 268-dealer network. As a result sales collapsed to 3462 in 1973 and 344 in 1975.