The calendar below shows the dates of when Mercury is in retrograde shaded in yellow. The letters in red are the days that they are most erratic, when Mercury is moving at its slowest, less than 1 degree each day. It is a time to plan more carefully. The grey areas on the chart, are the shadow period. It is marked as the beginning and ending of Mercury’s influence. Shadow period begins when the planet is at a position where it will later turn Direct. Shadow period ends when it returns to position at which it went retrograde. The retrograde cycle starts with warning shadow days. Then intensity will increase during the red letter or known as storm days. Things will then move into the heightened chaos of the retrograde. Mercury will then slow and the red letter days at the end of the retrograde period will finally tapering off from the effect during the closing of the shadow period. The days in red letters, are the days during which Mercury moves very slowly and thus greater intensity is exhibited of the things that Mercury does rule.
Read more about 'What is Mercury in retrograde.' Below are eastern stand times