Buffett, chairman and CEO of investment conglomerate Berkshire Hathaway (NYSE:BRK-B), is well known for both his astounding investment success and for sharing the secrets of that success openly with anyone who'll listen. And you'll know the ones who are keenest to listen – they'll be at their computers late on Saturday night or early on Sunday morning, eager to read what the Oracle of Omaha has to say.

His latest "Chairman's letter" to the shareholders of Berkshire Hathaway will be released at midnight on Sunday (AEDT), and is sure to be a doozy. Buffett will be reflecting on the half-century that he and business partner Charlie Munger have been running Berkshire – and this year we get two for the price of one (well sort of – the letter is available free!), with Munger himself also penning a letter taking the same retrospective approach.

A staggeringly successful role model

If you're not familiar with Buffett, he's no fly-by-night big shot or would-be hero. He's famous because of the simple, consistent, time-honoured investing approach he's followed for over five decades, and for the results he's achieved.

Warren Buffett has taken a small textile mill and made it into one of the largest companies in the world, in the space of 50 years. And in doing so, he's taken the book value – the sum total of its assets, minus its debts – of the company from US$19 per share to, wait for it, US$134,973 last year – a compound growth of 19.7 per cent annually. That sounds impressive, right? It is – the benchmark Buffett uses is the S&P 500. Its gain of 9.8 per cent per year is almost exactly half of Berkshire's. And it gets better: thanks to the miracle of compounding, 9.8 per cent per year since 1964 is 9841 per cent, but 19.7 per cent isn't just double that – it's far, far more… 693,518 per cent in fact!

If you'd have invested $10,000 with Buffett back then, you'd have $69.35 million today because not only has he generated outsized annual returns, but he's done it for a whopping 50 years! There's a reason he's widely regarded as the best investor we've ever seen… and he's not finished yet.

Investment advice from the master… free

When it comes to sharing what he's learned in more than 84 years, Buffett is extremely generous. He regularly appears on business news channels, writes op-ed articles for The New York Times and Fortune, and – perhaps most famously – those Chairman's letters to Berkshire shareholders… which are posted on the company's website for anyone to see, even if you're not a shareholder.

Buffett spends pages and pages helping you and me become better investors – free. He's waxed lyrical on derivatives (before the GFC), how to think about dividends, investor psychology and how he thinks about valuing businesses. Last year, he admonished investors who were focused on volatility in share prices and instead reminded us to fix our gaze on understanding the earnings power of the business itself.

Foolish takeaway

I'll be one of the diehard few up at midnight on Sunday (Saturday night, for the sake of avoiding confusion) taking in Buffett and Munger's best. I don't expect there'll be too many like me, but you should definitely take the time to read it. There are few guarantees in this life, but I'll give this one willingly – you'll be a better investor if you do.

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Scott Phillips is a Motley Fool investment adviser. He owns shares in Berkshire Hathaway.

You can follow Scott on Twitter @TMFGilla. The Motley Fool's purpose is to educate, amuse and enrich investors. This article contains general investment advice only (under AFSL 400691).