How is yahoo finance P/E Ratio TTM calculated?

Question

I'm a beginner in all these stats, but I understand PE Ratio as displayed on google finance, e.g for BP.L it's nearly 6.

However the stat seems different in yahoo finance, because it's PE TTM, where it is reported as 363! Then they have a "forward" P/E but that seems different too.

So how can/should the P/E ttm be interpreted? I presume the TTM is key and is what difference is to google finance. But having looked around i'm struggling to see why / how it's calculated. How can I get the "normal" (by normal i mean the one everyone refers to in the news etc) PE ratio from yahoo finance API? Perhaps I have to calculate it myself?

http://uk.finance.yahoo.com/q?s=bp.l&ql=1

Thanks, Dan

Answer 1

The correct p/e for bp.l is 5.80.

Bp.l is on the London stock exchange and prices are in local currency. The share price of 493 is reported in pence (not dollars). The EPS is reported in pounds. Using .85 pounds = 85 pence, you calculate the EPS as follows:

493.40/85 = 5.80 PE

Yahoo totally screwed up. They converted the .85 pounds into US dollars ($1.34) but didn't convert the 493 pence. By using the 493 as dollars, they got 493.9/1.34 = 368 pe!

Notice that Yahoo reports the American Depository Shares (symbol 'BP') with an EPS of $8.06. That correctly reflects that there are 6 shares of BP.l per ADS (1.34 * 6 = 8.04). But why is the share price listed at $46.69? Well...

493 GBp (pence) = 4.93 pounds

4.93 pounds = 7.73 USD

7.73 USD * 6 shares per ADS = 46.38 USD

Answer 2

P/E is Price divided by Earnings Per Share (EPS). P/E TTM is Price divided by the actual EPS earned over the previous 12 months - hence "Trailing Twelve Month". In Forward P/E is the "E" is the average of analyst expectations for the next year in EPS.

Now, as to what's being displayed.
Yahoo shows EPS to be 1.34. 493.90/1.34 = P/E of 368.58
Google shows EPS to be 0.85. 493.40/0.85 = P/E of 580.47
(Prices as displayed, respectively)

So, by the info that they are themselves displaying, it's Google, not Yahoo, that's displaying the wrong P/E. Note that the P/E it is showing is 5.80 -- a decimal misplacement from 580

Note that CNBC shows the Earnings as 0.85 as well, and correctly show the P/E as 580
http://data.cnbc.com/quotes/BP.L

A quick use of a currency calculator reveals a possible reason why EPS is listed differently at yahoo. 0.85 pounds is 1.3318 dollars, currently. So, I think the Yahoo EPS listing is in dollars. A look at the last 4 quarters on CNBC makes that seem reasonable: http://data.cnbc.com/quotes/BP.L/tab/5 those add up to $1.40.