Download Add in from below link. Before installing add in you must have install the extension Visual Studio 2010 Tools for Office Runtime
Click here to install "Visual Studio 2010 Tools for Office Runtime"
Steps to install.
1. Download exe file.
2. Run downloaded exe file.

File Version 32 Bit 64Bit
1.0.0.5 Download Download
To install below versions follow below steps.
1. Download .zip file.
2. Extract it.
3. Run setup file.
1.0.0.4 Download Download
1.0.0.3 Download Download
1.0.0.2 Download Download
1.0.0.1 Download Download