What are the best days and times to buy Delta flights

Ｔｈｅ ｃｈｅａｐｅｓｔ ｄａｙ ｔｏ ｂｕｙ Ｄｅｌｔａ ｆｌｉｇｈｔｓ ｉｓ ｔｙｐｉｃａｌｌｙ Ｔｕｅｓｄａｙ， ｗｉｔｈ ａｄｄｉｔｉｏｎａｌ ｏｐｐｏｒｔｕｎｉｔｉｅｓ ｆｏｒ ｓａｖｉｎｇｓ ｏｎ Ｗｅｄｎｅｓｄａｙ ａｎｄ Ｔｈｕｒｓｄａｙ. Ｔｏ ｍａｘｉｍｉｚｅ ｙｏｕｒ ｓａｖｉｎｇｓ， ｂｏｏｋ ｆｌｉｇｈｔｓ ａｔ ｌｅａｓｔ ｗｅｅｋｓ ｉｎ ａｄｖａｎｃｅ， ｔｒａｖｅｌ ｍｉｄｗｅｅｋ， ａｎｄ ｔａｋｅ ａｄｖａｎｔａｇｅ ｏｆ Ｄｅｌｔａ＇ｓ ｆｌｅｘｉｂｌｅ ｄａｔｅ ｓｅａｒｃｈ ｔｏｏｌｓ