Half of those surveyed with an investment portfolio were over the age of 60 while KiwiSaver membership was more skewed towards people aged between 30 and 50.
"It maybe that demographic have had investments for a longer period and understand the ups and downs of the market."
Previous research by the FMA has also shown the more involved a person is in investing, the more confident they are.
The research also found KiwiSaver providers had a poor perception among consumers for explaining fees clearly and helping people to understand why the investment was appropriate, although there had been an improvement on perceptions from the 2017 survey.
Robbers said changes to KiwiSaver provider statements this year to include fees in a dollar amount had helped but more needed to be done.
"While this shows that providers have done some work in this area, there is more to do.
"Explaining fees and whether a product is appropriate are the areas having the biggest impact on how consumers rate providers. Consumers agree with us that these factors are the best sign of whether providers are putting customer interests first and demonstrating good conduct."
Explaining why the product was appropriate was also ranked poorly by people with life insurance and had not improved on the prior survey.
Robbers said it showed the life insurance sector also had a lot of work to do.
"We know the terminology is difficult for people to understand as well as on the trust scale they are quite far down the list."
Overall the research found consumers are relatively satisfied with their financial providers with 70 per cent feeling that they are treated fairly and 72 per cent saying they are respected.
Eight out of 10 New Zealanders have at least one form of investment with KiwiSaver being the most common followed by life insurance.