I have a Google Analytics account with a well-functioning funnel made up of 4 goals. I can query the API and get the data out, but it does not match the funnel report in Analytics. Without getting into specific values, I can give you an example with faked data.

Here's how the funnel might look:

Shopping Cart
100 > 100 > 20
       80 (80%)

Address Page
5   >  85 > 25
       60 (71%)

Payment Page
2   >  62 > 10
       52 (84%)

Checkout
1   >  53
      (49.07% funnel conversion rate)

Okay, so you would expect the API to output data something like this:

goal1Starts goal1Completions goal1Abandons
100         80               20

goal2Starts goal2Completions goal2Abandons
85          60               25

goal3Starts goal3Completions goal3Abandons
62          52               10

goal4Starts goal4Completions goal4Abandons
53          53               0

Instead, it's different. Firstly, the abandons are associated with the following goal (so goal1 always has 0 abandons and goal4 always has >0 abandons. Okay, I can work with that. What's confusing is that the numbers are always a little different. The goal1Completions always match the report, as do the goal4Completions, but everything else is off by a small amount. Sometimes it's only 2 visits, other times it's off by 50.

For the report above here's the kind of results I would tend to get:

goal1Starts goal1Completions goal1Abandons
100         100              0

goal2Starts goal2Completions goal2Abandons
105         84               21

goal3Starts goal3Completions goal3Abandons
90          65               25

goal4Starts goal4Completions goal4Abandons
58          53               5

Here's what I know:

Goal(n)Completions + Goal(n)Abandons = Goal(n)Starts

Goal(n)Starts >= Goal(n-1)Completions

Goal(n)Starts - Goal(n-1)Completions != reported number entering at that level

That third one is particularly disappointing. So, here's my question:

What data do I need to pull from the API in order to recreate the counts in the Funnel report in Google Analytics? I don't need the pages exited to entering from - just the counts at every level.