Complex sentence: The 1876 development of refrigerated beef shipping, likewise, led to the modernization of that sector and by the 1920s, Argentine exports reached US $1 billion annually, of which 99% was agricultural.
Split into simpler sentences: The 1876 development of refrigerated beef shipping, likewise, led to the modernization of that sector. By the 1920s, Argentine exports reached US $1 billion annually, of which 99% was agricultural.