The EPS of Amazon for the last quarter of 2018 was $6.05. However, the P/E ratio is calculated using an annual number for earnings. Amazon’s earnings for 2018 was $20.14. (Source)
$1673 / $20.14 = 83.07
I'm not sure I agree with the implication, but I believe he is saying that if EPS grows by 40%, and you find that the current price of the stock has a P/E ratio of 40, then that is "okay and reasonable."
Let's say a stock was $10, and had a 10% EPS of $1 per share. Its P/E ratio would be 10.
Assuming the EPS grew 40% to $1.4 per share, T. Rowe Price seems ...
Fundamentally, the investor must decide how many years to look forward. A company is often valued at some-number-of-years times the current earnings.
But, for example, the company has $1 in earnings per-share and a 10% earnings growth and so include the 10% earnings growth by some means:
Valued at the current year's earnings along with four-year's forward ...
The price per earnings is the price divided by the yearly earnings.
The Earnings per Share of quarter 4 should could be a quarter of the total earnings. Add all of the Earnings per share for 4 quarters, and use that as the Earnings.