Its probably people just trying to spam with network with minuscule transactions with 0 fees, Itll clear up eventually.
False. Please do research before posting or not not post at all.
Full information can be found here.
In the website which you had posted above, the following information is given:
Quote
The fastest and cheapest transaction fee is currently 100 satoshis/byte, shown in green at the top. For the median transaction size of 226 bytes, this results in a fee of 22,600 satoshis (0.15$).
That means that transactions which paid at least BTC0.0002 in fee are getting confirmed without much delay (provided that their size is more or less equal to the median transaction size). The delay is mostly happening to those who paid a lower tx fee.