Warren Buffett’s Berkshire Hathaway reported more than $20 billion in equity investment gains for the second quarter, and over three-quarters of its stock portfolio were tied up in just five names. The conglomerate said approximately 78% of the aggregate fair value was concentrated in five companies during the April-June period. Berkshire reported a near $26 billion unrealized gain from its investments, and much of this gain came from its gigantic stake in Apple . The tech giant fueled the market rally in the second quarter, climbing nearly 18%. Berkshire’s Apple bet has ballooned to $177.6 billion. The Tim Cook-led company took a hit on Friday, however, after the company forecast a decline in revenue in the September quarter — which would be the company’s fourth in a row. The stock is still up 40% year to date. Berkshire’s Chevron stake was worth $19.4 billion at the end of June. The “Oracle of Omaha” trimmed the energy stock by $1.4 billion during the quarter as it underperformed this year. Shares of Chevron were down more than 11% this year, compared with the S & P 500’s near 17% gain. Longtime holdings Coca-Cola , American Express and Bank of America remained some of Berkshire’s biggest bets at the end of June. As always, though, the legendary investor asked investors to not focus on the quarterly fluctuations in Berkshire’s equity investments. “The amount of investment gains (losses) in any given quarter is usually meaningless and delivers figures for net earnings per share that can be extremely misleading to investors who have little or no knowledge of accounting rules,” Buffett said in a statement.