Here, in Brazil, the weather are most part of the time above than good... :)
Very few heli pilots are IFR qualified.
Only off-shore pilots flew IFR at all time in route.
At SBME, at this time the main AD´s for off-shore operations in the country, exists IFR IAC only for helicopters.
http://www.aisweb.aer.mil.br/_inc/carta-download.cfm?carta=E303CDED-D32C-4630-B26A47A009816C0C&d=tela
How much using IFR operations at this AD ?
Some between 30-40% of flights.