You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Adult_contemporary_music

Context:
The Hot 100 and Easy Listening charts became more similar again toward the end of the 1960s and into the early and mid-1970s, when the texture of much of the music played on Top 40 radio once more began to soften. The adult contemporary format began evolving into the sound that later defined it, with rock-oriented acts as Chicago, The Eagles, and Elton John becoming associated with the format.

Question:
During the middle and early parts of what decade did the similarity of Easy Listening and Hot 100 increase?

1970s