Berkshire Hathaway on Saturday reported a big rise in operating earnings in the fourth quarter, thanks to huge gains in its insurance business, while its cash pile expanded to record levels.

The Omaha-based conglomerate posted operating earnings — which refers to profits from businesses across insurance, railroads and utilities — of $8.481 billion in the quarter ending December. That’s 28% above the $6.625 billion from the year-ago period.

For the full year 2023, that brought operating earnings up to $37.350 billion, up 17% from $30.853 billion in the prior year.

Berkshire also held $167.6 billion in cash in the fourth quarter, a record level that surpasses the $157.2 billion the conglomerate held in the prior quarter.

Berkshire Class A shares have rallied roughly 16% this year.

Geico, the auto insurer considered Buffett’s “favorite child,” reported a profitable year, with net underwriting earnings of $5.428 billion in 2023. The improved earnings was driven by premium rate increases and lower claims last year.

Meanwhile, Burlington Northern Santa Fe (BNSF) reported full-year net earnings of $5.087 billion last year, a 14% drop from $5.946 billion in the prior year.

Insurance underwriting surged to $848 million in the fourth quarter, spiking 430% from $160 million from the year-ago period, driving operating earnings for the conglomerate.

Insurance investment income also rose to $2.759 billion on a quarterly basis, up 37% from $2.0 billion in the same period in the year prior.

But operating earnings from railroads fell in the fourth quarter, as it did in utilities and energy. Operating earnings from railroads dropped to $1.355 billion, down from $1.469 billion a year ago. Operating earnings for utilities and energy fell to $632 million, down from $739 million the prior year.

Overall Berkshire earnings, which include the company’s investment gains from publicly traded companies, more than doubled during the quarter from the year-earlier period, reaching $37.57 billion. For the full year, overall profits came in at $96.22 billion.

The conglomerate, however, included its usual disclaimer advising investors to look past fluctuations in quarterly results.

“We believe that investment gains and losses on investments in equity securities, whether realized from dispositions or unrealized from changes in market prices, are generally meaningless in understanding our reported periodic results or evaluating the economic performance of our operating businesses,” read a statement in the annual report.