Why is the Brazilian real currency split in 2 periods?

In Numista catalog the "Real" currency is split in two:
- From 1654 to 1790
- From 1790 to 1942
This division doesn't make any sense, if it was based in the copper currency it should be splited in 1799, and still it wouldn't make much sense since the changes that happened in 1799 were exclusive to the copper currency.
Can somebody explain me that?

Giovanni,

this is a good observation. It is divided in that way for a quite few years, as I am aware of.

It might be a little more detailed if we use the currency eras and the subdivisions listed by the Krause Catalogs:
- Real (Portuguese Colony, 1656-1822) 120 Reis = 1 Real
- Real (Empire, 1822-1833) 120 Reis = 1 Real
- Reis (Empire, 1833-1889)
- Reis (Republic, 1889-1942)

I will check that...