bath tub drain



My bath tub drain constantly clogs up and I constantly use the plunger
on it. Note:(the tub is used for showers 100% of the time) After I use
the plunger in the bath tub, it drains perfectly for about 3 or 4
weeks.
Do you think its a hair and soap build-up?..If it is, how can I clear
that up...thanks!

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