If you have reinstalled your Windows, you normally go about installing every software program one after the other. But in the case of your Windows Store apps, you need not do it the same way.
You can bulk install all the Windows Store apps which were installed on your previous installation of Windows 8, on your new Windows 8 installation too, with a single click.
To do so, click on the Store tile to open the Windows Store. Now right-click anywhere, and you will see a top bar appear. Click on Your apps.
Under Apps not installed on this PC, you will see a list of apps which have been purchased by you or which were installed on your Windows 8 PC.
From the bottom bar, click on Select all to select all the apps and next click on Install.
This will install all your Windows Store apps on your new PC at the same time. You need not install one app at a time. You can however, if you wish select only some of them and install only those from this list.
Hope this helps!