For our (Brown & Foucher) update to the top five net oil exporters paper, we are planning to look at cumulative remaining net oil exports versus annual export rates. A rough outline follows:

15 Gallons of Fuel in the Tank
Assume a car gets 20 miles per gallon, with a 15 gallon tank, and we embark on a five hour trip at 60 mph, using 3 gallons per hour. So we have five segments of one hour each.

(A)= Percentage of remaining fuel used in each one hour segment. (B) = Fuel used in each segment (always 3 gallons in this example). (C) = Remaining fuel in the tank at the start of each one hour segment. A = (B/C) X 100.

So, for the five segments we have:

(1) 20% = 3/15
(2) 25% = 3/12
(3) 33% = 3/9
(4) 50% = 3/6
(5) 100% = 3/3

We are of course out of fuel at the end of segment five, when we use 100% of remaining fuel in the tank. Note that the depletion rate increases with time.

Indonesia
Based on EIA data, from 1997 to 2003 (their last year of positive net oil exports), Indonesia (net) exported 1.148 Gb, a little over a billion barrels of oil, or 1,148 mb.  So, their remaining cumulative net oil exports at the end of 1996 were 1,148 mb.  We can of course very simply calculate the remaining cumulative net oil exports at the start of each year (C), and calculate the percentage of remaining cumulative net oil exports shipped in a given year (A), by dividing annual net oil exports (B) by (C) (X 100).  The data look like this:

End of 1996/Start of 1997:  1,148 mb in "Net oil export fuel tank"
1997:  21% = 243/1,148
1998:  29% = 259/905
1999:  34% = 221/646
2000:   42% 180/425
2001:  53% = 130/245
2002:  68% = 78/115
2003:  100% = 37/37
2004:  Net Oil Importer

Indonesia's net export fuel tank, based on annual data, was empty as of the end of 2003. Note that the depletion rate increased with time.

Top Five Net Oil Exporters (Saudi, Rus., Nor., Iran, UAE)
Based on EIA data, the 2006 to 2008 cumulative net oil exports from the top five fell between Sam's middle case and best case.  If we average his middle case and best case projections for post-2005 cumulative net oil exports, we get 117 Gb.   The EIA shows the following for annual net exports from the top five (2005 was about 8.8 Gb): 

2006:  8.5 Gb
2007:  8.0
2008:  8.2

Using 117 Gb for post-2005 cumulative net oil exports for the top five, the percentage numbers would look like this:

2006:  7.2% = 8.5/117
2007:  7.4% = 8.0/108.5
2008:  8.2% = 8.2/100.5
2009:  8.7% = 8.0/92.3*

*Estimated for 2009

At the end of 2009, based on the above numbers and based on 117 Gb, the top five will have shipped about 28% of post-2005 cumulative net oil exports.  

All of this is somewhat analogous to starting off with a full tank of gas and driving until you run out of gas.  At the start of the trip, the tank is 100% full.  At the end of the trip, the tank is 100% empty, but the point is that even as the volume of net oil exports shipped tends to decline, it appears that the percentage of remaining cumulative net oil exports shipped per year, i.e., the net export depletion rate, tends to increase with time.