So, who do you tip, how much, and when? Political Calculations treads these dangerous waters and offers the following (mostly serious) guidelines for answering these questions:

Tipping Guidelines
Who to Tip? (Profession)	How Much? (% of Typical Service Charge, or $USD Amount)	When?
Barber	100%	Once a year, typically in December.
Bartender	15%. Consider more if service is exceptional.	At each service.
Bus Driver	Consider a small gift instead of cash.	Once a year, typically in December.
Custodian	$20-$30	Once a year, typically in December.
Day Care Provider	$25-$70, also consider a small gift on behalf of your child.	Once a year, typically in December.
Dentist	0	If recent service was exceptional, consider sending a fruit basket for office.
Doctor	0	If recent service was exceptional, consider sending a fruit basket for office.
Doorman	$25-$100	Once a year, typically in December.
Dry Cleaner	$5-$10	If they can get a difficult stain out of your clothing, once per occurrence.
Economist	0	Never tip an economist. It only invites a lecture on the economic theories of tipping and nobody has that kind of time.
Engineer	0	Consider giving a new high-end technology device at each major holiday instead.
Facialist	10%	At each service. Also consider $10-$20 in December.
Food Delivery Man	15%	At each service.
Garbage Collector	$10-$20	Once a year, typically in December. Don't place tip inside garbage container.
Gardener	One week's salary	Once a year, typically in December.
Gym Locker Room Attendant	$5-$10	Once a year, typically in December.
Hairdresser	10%	At each service.
Hotel Bell Staff	$1-$2 per bag handled	At each service.
Hotel Concierge	$5-$10	Every time they perform a task. $20 is appropriate if the task is difficult.
Hotel Doorman	$1-$3	Only for hailing a taxi.
Housekeeper	1-2 week's salary	Once a year, typically in December.
Mail Carrier	Less than $20	Once a year, typically in December.
Maitre d'	$20	At each service. If you are regularly greeted by name and provided with your preferred table, consider $50.
Manicurist	10%	At each service.
Nanny	1-4 week's salary	Once a year, typically in December. Also consider a small gift on behalf of your child.
News Carrier	$15-$25 (for daily delivery)	Once a year, typically in December.
Package Delivery	$10-$20	Once a year, typically in December, if service is provided by same individual throughout the year.
Parking Garage Attendant	$10-$30	Once a year, typically in December.
Personal Care Provider	1 week's salary	Once a year, typically in December.
Personal Trainer	100%	Once a year, typically in December.
Pest Control Service	100%	Once a year, typically in December.
Pet Groomer	$20	Once a year, typically in December.
Politician	Varies	To be perfectly honest, a 'tip' for a politician is more often called a 'bribe.' If you must, you may obtain maximum value for your 'tip' by recording the transaction, and video with excellent sound quality is essential....
Pool Cleaner	100% ($20 minimum)	Once a year, typically in December.
Superintendent (Building)	$30-$100	Once a year, typically in December.
Supermarket Bagger	$10-$20	Once a year, typically in December.
Supermarket Butcher	$10-$20	Once a year, typically in December.
Supermarket Checker	$10-$20	Once a year, typically in December.
Teacher	$10-$25	Once a year, typically in December. Also consider a small gift on behalf of your child.
Tour Guide	$5-$10	Once per day.
Waiter	15%-20%	At each service. Consider more if service is exceptional.

- posted by Ironman at 6:30 AM | Permalink | |