At what point in the solar cycle does the 20-meter band usually support worldwide propagation during daylight hours?

Explication

At 14 MHz the 20 meter band normally stays below the daytime F2 MUF even when solar activity is low, so it supports long-distance daylight paths at any point in the cycle. Solar maximum improves it and opens higher bands, but 20 meters does not depend on maximum conditions to work.