World Cup Sunshine

A water-tight theory, I was inclined to think at the time... but could it actually be proved? It got me thinking: was there any direct correlation between the amount of sun that shone during a World Cup and the quality of the football it produced?

Obviously it was never going to be easy calculating the exact amount of sunshine for a single match, let alone several tournaments. No-one to my knowledge has deliberately stuck a light meter in the pitch of every World Cup game and published the readings for all to see, so how could the theory stand up to assessment?

I soon realised this was no place for exact science and academic brilliance. Some wide-ranging assumptions and flabby rules were needed if this exercise was going to bear fruit, so that's exactly how I went about my work.

To begin, there's no quantifiable way of determining how good a World Cup tournament is or was. Every one of them has had its fair share of memorable moments, but they've all had their dull matches too. For the purposes of this elaborate plan, therefore, I decided to focus on the number of goals scored during a tournament as a general gauge for its overall quality.

Then there was the sunshine issue. What was it about, say, Mexico '70 that proves it was so rich in sunlight? In short, shadows. Seemingly every image we saw of Pele or Gerd Muller or Jeff Astle (for instance) featured said players with short, dark shadows attached to their feet, and it's these shadows that confirm the presence of strong sunlight.

But could a match be considered 'sunny' if, for instance, the sun only shone for five minutes of a match? In my view, no: the term could only be applied if shadows were being cast on the pitch for more than half a match.

And how could I prove that this was the case? By watching YouTube videos that, in some cases, lasted no more than a couple of minutes.

(I did warn you that this was unscientific.)

In my defence, however, many World Cup matches can be found on YouTube in their entirety, and where this was the case, I assessed the whole game to reach some sort of outcome.

Oh, and I also decided to start my research from 1970. My reasons were two-fold; firstly, because the number of World Cup matches on YouTube falls away sharply before the first Mexico tournament, and secondly, because all pre-1970 TV footage is in black and white. The latter point is apposite when trying to work out whether a match is played in hazy sunshine or no sunshine at all.

Finally, I had to list all the important details for each of the games. Initially, I planned to record each World Cup match as being 'sunny', 'cloudy' or 'rainy', but I soon realised this was too complicated. All that was needed in essence was to say whether a match was 'sunny' or 'non-sunny', so that was the system I chose.

Not that these were the only classifications, of course. Many World Cup matches are played at night, so for the purposes of this exercise, the label 'Night' was applied to all games that kicked off from 7pm onwards in the local time zone.

And for even more complication, some games have been played in a stadia with a closed roof. For those matches, the label 'Indoor' was applied.

Data collecting

Having determined all of the above, it was time to start collecting the data... from 636 matches. A spreadsheet was created, and one by one, each game was listed along with its duration and goals scored (including extra time but not penalty shoot-outs).


Once all the data was collected (and I say that as if it only took me ten minutes), it was simply a case of totalling up all the goals and minutes for each match in each category of Sunny, Non-Sunny, Night and Indoor.

It was at this point that I felt an infographic coming on. Here it is:

Click for larger version

Thanks to the loose application of some tenuous (at best) rules based on many all-too-brief video clips, a number of conclusions were drawn from the data.

Conclusions

Firstly, the answer to the big question: does a World Cup football match played mostly in sunshine bring forth more goals? The answer, it seems, is a definite 'no.' Of all the four match types, 'Sunny' came out worst with one goal scored every 37.5 minutes. 'Non-Sunny' matches (i.e. those played in cloudy or rainy conditions) featured goals scored (roughly speaking) once every 35.3 minutes - about the same for 'Night' matches.

Best of all, however, were the 'Indoor' matches. So far, there have been 12 games played in stadia with a closed roof, and in those, a goal has been scored once every 29.2 minutes.

(Once again, it behoves me to remind you that these are very imprecise figures, but unashamedly so. And can you find any that are more accurate on the internet? Of course not, for no-one has such dedication to a redundant cause as I.)

Taking each tournament in sequence, you can see from the infographic that the 1970 World Cup was indeed dominated by 'sunny' matches (as shown by the yellow blocks in each case). As we suspected all along, Mexico came up trumps again in 1986, and proportionately these two tournaments had the highest percentage of 'sunny' games out of all the twelve World Cups covered (see separate graphic below).

Click for larger version

Sunshine was in the shortest supply during the 2010 World Cup with the 1974 competition not far behind. In general, however, there have been far fewer 'Sunny' games since the start of the 21st Century - not necessarily because of adverse weather conditions, but because more World Cup matches are being played later in the day in stadia that don't allow direct sunshine to reach the pitch quite so easily. Both factors mean less sunshine is seen in quite the same way as we saw back in 1970.

Taking all 636 games in their entirety, we can generally see that there's almost an equal three-way split between those that were 'Sunny', those that were 'Non-Sunny' and those that were played at night. To be a little more specific, however, the 'Sunny' games just about have the lion's share - 38% compared to 32% for 'Night' games and 28% for 'Non-Sunny' games.

Finally, to confirm the earlier point, you're likely to see more goals in 'Indoor' matches - 3.17 on average, compared to 2.45 in 'Sunny' matches. And that, as much as anything, sums up the overall result of all this research and analysis: as much as we choose to disbelieve it, 'Sunny' World Cup matches are somewhat inferior where the quantity of goals is concerned.

A depressing thought, but the one thing this exercise can't quantify is the quality of the goals scored during sunny World Cup matches. Without spending several more weeks on research, I'd like to offer the following names to make a case for the sunshine/great goals ratio: Josimar, Pele, Maradona, Krol, Negrete...

Need I go on?

-- Chris Oakley