My source is myself. 175 websites, 150.000/200.000 unique visitors by day on my network, targeting about 100 different keywords in 3 languages for searches always with more than 10 million competitors results.
The activity at more than 60 search sites makes up the total search volume upon which percentages are based -- 4.3 billion searches in this month.(may) - source: Nielsen
Your query sample represents: 100 different keywords / 4,300,000,000 searches ~ 0.000000000233% of searches. (Please, note I did not take into account the foreign searches, so the sample size compared to all searches possible, is actually smaller than stated.)
317,646,084 domains registered - Source Internet Domain Survey, Jan 2005, Internet Systems Consortium.
Your domain sample represents: 175 domains / 317,646,084 domains ~ 0.000000005509% of registered domains.
Not sure the sample sizes are quite large enough to be conclusive.