1. First I will ask clarifying questions.
2. Next I will brainstorm calculations, fill in estimates/assumptions and calculate.
4. Last I will evaluate if the answer is reasonable and identify areas of potential error.
1. To confirm, time spent responding to prompts from automated machines and punching numbers in keypad does not count? Correct
2. Automated systems can include: department stores, DMV, e-z pass, schools/universities, FedEx/UPS, cable/phone companies, any more I should be thinking of? That is a good start
Brainstorm calculations, fill in estimates/assumptions and calculate
(300M people in the US) (% of people who call automated places per day) (average number of time spent on hold)
(300M people in the US) (40% of people call automated places per day) (7 minutes on hold) = 840M minutes
840M minutes / 60 minutes per hour = 14M hours a day on hold in the US
40% can be overestimated, many answers to consumer questions can be found online, on the party's website.
7 minutes can be overestimated, some companies have the option where customers input their phone number and the company calls the consumer.
I did not factor in the percentage of times that the call gets disconnected and the consumer has to wait on hold all over again.
14M hours/day seems like a lot, I would reduce the percentage of folks who call automated systems and the average time spent on hold. I would factor in a 5% chance of the line getting disconnected and folks have to call back and wait on hold again.
(300M people) (25% who call automated places a day) + (5% of the 25% who have to call back) (4 minutes on hold) =
75M people call automated places a day + 37.5M people who have to call = 112.5M people calling automated places a day
(112.5M) (4 minutes on hold) = 450M minutes
450M minutes/60 minutes per hour = 7.5M hours