This year's National Day Rally (NDR) will take place this Sunday (Aug. 20). It will be the 14th time Prime Minister Lee Hsien Loong addresses the nation.

This means that he has worn 13 different outfits to the previous 13 NDRs.

Have a look at his fashion from 2004 to 2016:

And here are some of our observations:

PM Lee only wore pink twice

Contrary to the belief that Lee is always decked out in pink, you may be surprised to know that he has worn pink for the NDR only twice: in 2010 and 2013.

In a Facebook Q&A held in 2015, he was asked why he was often seen in pink shirts. He said it was a decision made by his TV producer.

2008 is an anomaly

Most of Lee's shirts can be classified under red or blue tones. We know this because we plotted them out on a colour wheel.

The red tones are labelled in white, and the blue tones are labelled in black. This should give you a rough idea on how the colours are distributed every year.

2008 lies somewhat anomalously in between the blue and red shades. This is how the shirt looks like:

It seems like a mix of grey/violet/brown. We don't really know.

He prefers red tones and has worn them consecutively

Out of 13 rallies, he wore a shirt with a red tone 7 times (2004, 2006, 2009, 2010, 2012, 2013, 2015). The shades of red vary between brown, maroon, bright red and pink.  In contrast, he wore blue tones only five times.

Lee also wore red tones for two consecutive years in 2009-2010 and 2012-2013. This has never happened with a blue shirt.

He's not a fan of patterns and prints

A striped shirt appeared for the first and last time in 2005. Other than 2005, the rest of his shirts were block-coloured. Guess he's not a fan of patterns and prints.

The last time he wore spectacles was 7 years ago

Lee has not worn spectacles to the rally since 2010, but what got us interested was the evolution of his spectacles over the years.

In 2007, it was replaced with a sleeker-looking pair with a frame that was less squarish compared to its earlier counterpart:

It looks like Lee has varied his NDR look in the last 13 years, but one thing has remained constant though.

And that's his hairstyle.

Top photo adapted from screenshots of the National Day Rally on Youtube, colour wheel from Pinterest.

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