IncrementalPCA explained_variance_ratio_ calculation

[krstopro]

Why is explained_variance_ratio_ calculated differently in PCA

scikit-learn/sklearn/decomposition/_pca.py

Lines 557 to 559 in 8721245

	explained_variance_ = (S**2) / (n_samples - 1)
	total_var = xp.sum(explained_variance_)
	explained_variance_ratio_ = explained_variance_ / total_var

and IncrementalPCA?

scikit-learn/sklearn/decomposition/_incremental_pca.py

Line 354 in 8721245

explained_variance_ratio = S**2 / np.sum(col_var * n_total_samples)

Is it because of the correction factors used in IncrementalPCA?