Insane weight fluctuations

One trick if you weigh daily. Log your results in a spreadsheet, and in the adjacent column calculate a 7 day average of the previous 7 day's readings. This smooths everything out.

Example:

Notice how the second set of numbers clearly shows progress, with no weight gain, whilst the 1st set varies much more.

Recorded Daily Weight (lumpy, blue line on graph)
87.8
89.5
89.1
88.6
87.6
88.4
87.6
87.4
87.3
87.1
87.5
87.0
87.7
87.6
87.4
86.8
86.8
86.8
86.7
85.8
86.0
86.4
86.1
86.0
85.7
85.2
84.8
85.2
85.4

7 Day moving average (red line on graph)
88.4
88.3
88.0
87.7
87.6
87.5
87.4
87.4
87.4
87.3
87.3
87.2
87.1
86.8
86.6
86.5
86.4
86.3
86.1
85.9
85.7
85.6
85.5