Under conditions of high and medium ZIP+4 usage, high savings, and high multi-line performance, option D (automatic conversion) has about a 5 percent and 11 percent higher NPV, respectively, than option A (single-line OCR). At low ZIP+4 usage, another things being equal, the option D advantage increases to a substantial 134 percent or about $820 million in NPV. At a low savings rate (along with low ZIP+4 usage and high multi-line performance), the relative advantage of option D over A increases further to about 310 percent although the absolute advantage decreases to about $650 million in NPV. Even at low multi-line performance, with low ZIP+4 usage option D has a 53 to 119 percent relative advantage in NPV and a $320 to 250 million absolute advantage in NPV,
at a high and low savings rate, a higher NPV than option A procurement) has a significant low ZIP+4 usage.
respectively. Option H (90-10 split procurement) also has
under almost all conditions.
(50-50 split option A at
The net NPV advantage or disadvantage of options D, G, and H compared to option A is shown in figure 12 for various conditions. Relative as well as absolute comparisons
are included for low ZIP+4 usage. The results clearly show that options D and H have
marginally higher NPV at high substantially higher NPV at low
and medium ZIP+4 usage
under all conditions other hand, option G
a a a
marginally lower NPV than option A at high ZIP+4 low or median multi-line performance, a marginally and high ZIP+4 performance, and a substantially conditions.
usage and median ZIP+4 usage with higher NPV at median ZIP+4 usage higher NPV under all low ZIP+4
Another way to present these results is shown in figure 13. Here, the 80 percent credible values are shown for each option along with the overall net present value for