Book Value Per Share growth

I am wondering if you can help explain how the Book Value Per Share in the financial accounts grows.

From what I have learnt in P2 so far, the book value per share is simply equity attributable to shareholders/no of shares in issue.

And thus I would have thought by definition we we expect the book value per share to grow by the Earnings Per Share – the dividends paid, as this will be the amount retained earnings increases by.

But when I look at real companies financial accounts, like the company I work for, this does not tie up and I can’t understand why? From the above logic I should be able to calculate the EPS by taking the growth in the book value between years and adding back dividends paid but it never matches up.

Is there anything else affecting this?.