问题
i am working on an application that uses the Google Analytics Export API and i am trying to get the "Trend" result that Google shows against each of your site accounts as a percentage
ie UP 35.04% or DOWN 16.02%
How/where do they get this figure and is it available in the API somewhere.
i have tried comparing averages of last month to this month/first week of the period vs last week of the period etc, but i cannot seem to get the same numbers that Google provides.
any ideas?
thanks in advance Doug
回答1:
The formula is pretty simple (excluding today's data):
(Visits over the last 30 days - Visits between 31 and 60 days ago) / (Visits between 31 and and 60 days ago).
You can see it in action in the interface if you go to the default dashboard, where it shows you the last 30 days, then on the calendar, click "Compare to past" and select the default amount. It'll show you the numbers used for each calculation and the calculations as they appears in that account list.
The API does not, however, expose pre-calculated numbers (for example, they don't compute bounce rate for you; they just give you the pieces for it.)
So, you'd need to do two API requests to get this data. One for ga:visits in the last 30 days, and then one for ga:visits in the 30 days prior.
Then, when you get it, just subtract, divide, and multiply by 100, and you'll have the percent you're looking for.
UPDATE: The striked out part of the answer was true, but is no longer. The newest version of the Google Analytics API does provide access to some pre-calculated values.
来源：https://stackoverflow.com/questions/4614399/using-the-google-analytics-export-api-to-get-a-websites-trend