The speed that you snowshoe at (the distance covered in a period of time) will vary greatly depending upon a number of factors. Snow conditions, your effort and fitness level, and weather are three of the most influential variables affecting speed.
Snowshoeing speed will be most greatly influenced by the snow conditions of the route you are on. These snow conditions are constantly changing. One day you may have a fast packed trail where you might be able to snowshoe at a speed of four miles an hour walking fast or eight miles an hour or faster if you are running. The next day, after a 14-inch powdery snowfall, your speed might be cut to under one mile in an hour on the same route while expending great effort to break trail.
Snow conditions can also change dramatically during the day. It may take you an hour to snowshoe up to a favorite spot, but your return trip may take twice as long if the wind picks and/or new snow falls and your trail is covered. Or, your return trip may take less than half as long if you broke trail in deep snow up to a specific destination and can follow your tracks out.
It is difficult, and misleading, to compare one day of snowshoeing to another, snowshoeing to just hiking or running without snow, or even the snowshoe efforts of two people covering the same route on snowshoes at different times. Thus those that record their activity in a daily diary may find it more useful to record the time, effort level and snow conditions for snowshoeing entries rather than just writing down the distance covered.
No other form of human powered transportation has its speed influenced so greatly by external factors as does snowshoeing.