I have been doing genealogy research for more than 10 years off and on. It has taken this long to get the result shown below: almost 7 generations completely documented (12 missing people out of 127).
Fan Chart for Kevin Thompson
From the additional charts below centered on my grandparents, you can see that in some areas much more than 7 generations are known.
Fan Chart for Clark Minard Thompson
Fan Chart for Evelyn Thorst Erickson
Fan Chart for George Avner Baldwin
Fan Chart for Adda Wanda Anders
If you have done serious genealogy research for any length of time, you know that these charts are definitely a reward in themselves...