I think Return on Equity is the single most important metric to look for when investing. Company with high ROE means company can make lots of profit with as little equity as possible. Every year or every quarter, company's profit will be kept on equity, inside Retained Earnings. The bigger the profit each year, it will make equity bigger and bigger as well. ROE can be bigger when company take advantage of Debt (hutang), as long as operation net income can be higher than interest cost (biaya bunga).

Shareholder equity comes from Equity (modal) + Additional paid-in capital (tambahan modal disetor) - Treasury stock. If company do a buyback (therefore treasury stock is added), in the same time company's equity is also be taken out. Therefore it makes ROE bigger. So when company's equity is reduced, we need to check again.