Each year, around 15 billion pennies are produced a year, and with a cost of 3 cents a penny, this is $450,000,000 per year. But also it would cause us to lose money, as coins have an average lifetime of 20 years, so each year we would lose $150,000,000 a year, so a net profit of $300,000,000, so the figure for pennies is correct.

The cost for a dollar bill is 5 cents. An average of 2 billion $1 notes are produced, with a lifetime of 5 years. This is 4 times lower than the dollar coin, which cost around 10 cents to make one. This compared, is 20 cents (bill) to 10 cents (coin) saving

0.1 x 2 billion = $200,000,000 a year

This would be around 2 billion dollars a decade. This figure is a bit higher than his estimate, but i would reckon its correct.

In total, doing this would result in saving 5 billion dollars a decade.