The amount of monthly data usage by a sample of $10$ cellphone users $($in GB$)$ is shown below.

$0\mathrm{.}5,1\mathrm{.}3,6\mathrm{.}8,2\mathrm{.}4GB,1\mathrm{.}5,6\mathrm{.}6,1087,1\mathrm{.}8,4\mathrm{.}4,5\mathrm{.}4$

Identify potential irregularities in the data.