Wrong number of users in channels reported by Directory feature

Description:

Directory shows list of channels and number of users in each channel.
Numbers are wrong.

Steps to reproduce:

1. Go to Directory -> Channels
2. Check number of users
3. Go to channel
4. Check info

Expected behavior:

Number of users match

Actual behavior:

Number of users doesn't match

For example, general channel

Directory listing reports 6002 users.

Channel info reports 69813 (proper value).
There are also channels where directory reports negative number of users:

While in fact there are 202 and 450 users respectively.

Server Setup Information:

• Version of Rocket.Chat Server: 1.0.3 (same issue was before upgrade)