Before turning 93 on Wednesday, Warren Buffett made a number of astute moves in the past 12 months that helped push his conglomerate Berkshire Hathaway to an all-time high. Many Buffett watchers have been dazzled by the “Oracle of Omaha’s” sharp mental acuity and astute investments he’s able to pull off. His active engagement enabled Berkshire to climb to a new peak and enjoy record operating earnings. Here’s a recap of Buffett’s significant moves during the period. Buying T-bills Buffett’s massive cash hoard swelled to nearly $150 billion at the end of the second quarter. Unlike previous years where a surplus of cash made him nothing, he’s been earning a sizable return over the past year from buying short-term Treasury bills. The investing guru recently revealed that he’s been buying $10 billion worth of 3-month and 6-month T-bills at the weekly government auctions every week. Presumably Berkshire rolls over its maturing T-bills by buying new ones. Earlier this month, Buffett shrugged off Fitch’s U.S. credit rating downgrade , saying he continued to buy Treasuries every week. “Berkshire bought $10 billion in U.S. Treasurys last Monday. We bought $10 billion in Treasurys this Monday. And the only question for next Monday is whether we will buy $10 billion in 3-month or 6-month” T-bills, Buffett told CNBC. Ramping up Japan bet Buffett recently hiked his stakes in five Japanese trading houses — Itochu , Marubeni , Mitsubishi , Mitsui and Sumitomo — to more than 8.5%. Buffett even traveled to Japan, his first time in more than 11 years, to meet with the heads at these firms. Social Capital’s Chamath Palihapitiya expressed his admiration after analyzing his latest bet on Japan , calling Buffett “the greatest of all time” The technology investor said the five Japanese trading houses Buffett invested in are good investments because they pay stable dividends and boost their earnings, at the same time as Buffett was able to hedge currency risk by selling Japanese debt. “It’s inspiring to see folks act this intelligently at scale,” said Palihapitiya. Occidental stake tops 25% Buffett also kept buying the dip in Occidental Petroleum , now owning a quarter of the oil giant. The buying spree came as Occidental shares pulled back after a stellar 2022. The stock is down 1% in 2023 after soaring 117% last year, becoming the best performer in the S & P 500 for 2022. Occidental, once known for being founded by legendary oilman Armand Hammer, is now Berkshire’s sixth-biggest equity holding. Buffett has ruled out the possibility of taking full control of the energy company. The legendary investor previously revealed that he started buying the stock after reading through Occidental’s annual report and gaining confidence in the company’s growth and its leadership. Betting on homebuilders The conglomerate picked up shares of a few homebuilders in the last quarter – D.R. Horton , NVR and Lennar . These stakes are relatively small for Berkshire, so they could have been purchased by Buffett’s two investing lieutenants, Todd Combs and Ted Weschler, who oversee about $15 billion each. The bet comes at an interesting time for the housing market where sales of newly-built homes have remained strong despite a surge in mortgage rates. Buffett’s sprawling conglomerate is no stranger to the homebuilding industry. Berkshire bought Clayton Homes 20 years ago for $1.7 billion, and also owns paint company Benjamin Moore. Investing in LNG Buffett’s big energy and utility division Berkshire Hathaway Energy has agreed to purchase a 50% stake in the Cove Point liquefied natural gas facility for $3.3 billion in cash. Some said the deal builds on a growing bet on energy infrastructure at the conglomerate as it gains control of one of the rare functional facilities in the U.S. that can export LNG.