Rounds are worth what someone is prepared to pay for them.
I sold a large round last year where the majority was council/ex council for close to 8x the monthly take.
It's about varying factors such as how long the round has been established for, how compact the work is, prices, yeild per hour and most importantly,the relationship you have with teh customer.
All of the above were rock solid with absolutely no messers or difficult payers, they were weeded out over 7 years by myself.
Just for the record,the lads that bought the work have returned it to trad after 5yrs WFP and have added 30% to the round.