Falling Downloads and Earnings

It appears that you don't have a large enough portfolio to earn a regular stream of sales. As your portfolio grows and you diversify your assets, your sales should become more regular.

Like others said, it's normal Ahmed. 

Set yourself the goal of creating a certain amount of work every month, and stick to it.

For me is 100, and the more I do it the more I learn what sells best.

Whatever you do, don't let anyone discourage you!

Cheers!

The reason for this is that there are fluctuations, based on your content, the competition and the buyer's needs. This is normal, and except for adding continiously more high quality assets, you won't have an influence on this.

It's the nature of the beast! The market is fickle. You win some, you lose some.

No one can make a judgment based on this information alone.
One thing we can say is that by registering a large number of assets in many genres, the number that will sell on average will increase.
There are assets that sell more easily depending on the season, and assets that sell throughout the year.