40 Billion is too low for a 5 year upgrade. Why? here:
from skyscrapercity forum:
The cheapest modern warship cost $175-200 million and that is the Chinese/Pakistani F-22P Zulfiquar anti-submarine guided missile frigate while the US Navy Arleigh Burke class Aegis guided missile destroyer cost $1.8 billion.
The cheapest modern submarine is the Russian Kilo class ($350 million).
credits to @gmaer.