The
link is here.
The guy claiming 99 mpg is no longer cited (he may still be there but has revised his entry!)
I looked at some of the current entries. The top one claims 66.8 mpg (~3.56 l/100 km) over 30,000+ miles 100% city driving, with one tankful going up to 74.6 mpg (3.18 l/100 km). Quite frankly, I find this incredible in a car not really suited for town work.
Another guy did almost as well but with 75% highway. He inflated his tyres to some phenomenal pressure.
At the other end of the scale, the guy with a 11,000 miles+ averages 35.6 mpg (6.67 l/100 km) lives in the Rockies in BC and I can understand that his problem is, as I observed, hill climbing really does push the consumption up.