To better understand the contribution distribution, we need a new column that shows the ratio of private contributions (py) to total contributions (tc).

Formula: (totalPrivateContributions / totalContributions) * 100

Proposed Implementation:

1. Add totalPrivateContributions calculated field to DevIndex.model.Contributor.
2. Add privateContributionsRatio calculated field.
3. Add 'Private %' column to DevIndex.view.home.GridContainer, positioned after 'Total'.