In this edition of More or Less, David Edmunds asks, how do you make your artwork more valuable?

Hello and welcome to More or Less on the BBC World Service, where you'll weekly guide to the numbers all around us.

I'm David Edmunds. My wife says I'm no oil painting, but this week I'm taking the big picture of the art market.

If you want to die in poverty, take a lead from the 19th century Dutchman Vincent Van Gogh and become an artist.

Naturist Lee Van Gogh remained poor throughout his life and most artists struggle to make a living.

On the other hand, the global art market is now huge, where for staggering $63.7 billion in 2017.

And some artists do very well.

So, thank you Charlie.

But what drives the price of art in auction? Well, principally of course, its quality.

But beyond that are there tips for auctioneers, or artists, or buyers of art, on how to maximise their sale price or their return on investment?

Rachel Poundle is Professor of Finance at Maastricht University in the Netherlands and specialises in the art market.

Here is a countdown of six tips and suggestions.

Tip 6, sell on a sunny day.

Okay, so it's easier to depict a sunny day on canvas than to control the actual weather.

But Rachel Poundle says there appears to be a sunshine premium.

In the art market, you would think that people aren't necessarily prone to changes in the weather, but they are of course very emotionally driven.

So one study that we did a few years ago was looking at the prices in London when there was exceptionally good weather.

So what we found is that paintings that sold in the winter period on a particularly sunny day were 3 to 4% higher.

This wasn't the case at the top end of the distribution where again, perhaps buyers have a lot more self-control.

They've set themselves a limit potentially, but was driven at the bottom end of the market.

Tip 5, buy contemporary artists.

It's riskier, but for a chance to make a big return on your art investment, acquire the work of a modern artist.

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