Founders' Reward Question

I read here: Continued Funding and Transparency - Electric Coin Company that the investors part of the Founders’ Reward (1.65% of the total coin supply) will be mined to them in the first year. That is 346,500 ZEC in the first year. How many coins will be mined in total after the first year? Percentage wise, do you think there is a risk of investors dumping their coins?

I’m less concerned with the part of the Founders’ Reward that goes to the actual devs and founders because they are so closely tied to the project and they will be receiving their chunk over 4 years so it will be more distributed. But investors who may not care about the project receiving all their coins in the first year could put pressure on the market. Does anyone know what percent of coins in existence the investors will have by the end of year 1?