By the early 1970s, softer songs by artists like The Carpenters, Anne Murray, John Denver, Barry Manilow, and even Streisand, began to be played more often on "Top 40" radio and others were added to the mix on many AC stations. Also, some of these stations even played softer songs by Elvis Presley, Linda Ronstadt, Elton John, Rod Stewart, Billy Joel, and other rock-based artists.
Is there an answer to this question (If it cannot be answered, say "unanswerable"): During what period were artists like Anne Murray and Barbra Streisand featured on Top 40 radio?
the early 1970s