Though these nickel coins are very modern, Monaco is a tiny, tiny country. Not a lot of coins are required for there to be enough to go around for all of its citizens. This means that mintages for most years stay very low, and this provides these coins with a value due to scarcity as collectors of world coins seek to complete their collections.
Approximate catalog values for most years go like this:
worn: less than $1 US dollar approximate catalog value
average circulated: $2
well preserved: $5
fully uncirculated: $12
Coins dated 1971, 1974 or 1982 (your coin Spencer, sadly) are common; divide the above values by 2 for coins of these dates. The exception is for 1982 dated coins that are absolutely, fully uncirculated, which catalog for the usual $10 US dollars.
Remember that these are catalog values (see our 'Important Terminology' page on the top left) and only apply to problem-free coins that are not scratched, gouged or stained.