The TRUTH About Steamers and Drifters

In this article I am going to look at market movement between the bookmaker’s opening show and the final Starting Price and unearth some truth about steamers and drifters, writes Dave Renham.

In what follows I will be focusing on flat and all-weather racing in the UK spanning five years from 2018 to 2022. Bookmaker data is taken from William Hill.

Typically, the opening show tends to be around ten minutes before the off, and these are the initial prices the bookmakers set. Backing a horse at ‘opening show’ and seeing it shorten in price means you have probably gained a decent edge and potentially some value. Conversely, if you take the opening show price and the horse drifts (lengthens) in price, then you may have lost some value.

However, it is important to note that more horses will lengthen in price than shorten. Here is a graphic to illustrate this by looking at the percentage of all runners that either shorten in price, stay the same, or lengthen in price:

 

 

As can be seen nearly 42% of all horses drift, compared with 34% who shorten. Roughly a quarter of all runners see their price remain steady. It is interesting to note that the percentages are very similar when comparing handicaps with non-handicaps (within 1%), hence the market behaves in a very similar way from opening show until the off regardless of race type.

My starting point for researching this article is very simple – look at opening show versus Starting Price and seeing what effect the differential has on strike rate and profit/loss. In terms of profit/loss I am going to calculate returns to Betfair Starting Price. For the sake of simplicity, I am going to split the runners into three groups:

 

- horses that shorten in price from opening show

- horses that stay the same price as opening show

- horses that lengthen in price from opening show.

 

Using numerical examples:

 

 

Let me start by looking at all races.

 

 

As we can see, horses that shorten in price have comfortably the best strike rate, therefore, unsurprisingly, the market does tend to get it right most of the time. In terms of returns to Betfair Starting Price horses that have remained the same price have proved the best value by a couple of pence in the £. It may be interesting to note that there is little in it between horses which shortened in price compared with those which lengthened.

So, we have a very even looking starting point in terms of returns / value, now it is time to dig deeper.

Horses whose opening show price was 4/1 or shorter

I thought it made sense to look at different price brackets so let’s start with the better fancied runners. It also seemed logical to use the opening show price for this rather than SP as the opening show price is known pre-race. Here are the splits:

 

 

There is the same sliding scale in terms of strike rate, but it is the horses that lengthened / drifted in price that have been better value this time. Horses that shortened in price proved the worst value.

 

Horses whose opening show price was 4/1 or shorter and then lengthened in price

Focusing on this subset of drifters, it is interesting when you compare the results on Grade 1 tracks compared with other tracks. The Grade 1 tracks on the flat are Ascot, Doncaster, Epsom, Goodwood, Newbury, Newmarket, Sandown and York. Firstly, let’s review the win and each-way (win + placed) strike rates:

 

 

There is a difference of 1.6% in the win strike rates; 4.3% in terms of combining win and placed percentages (each way). These differences may look quite modest, but they are significant.

The graph below shows the return on investment (ROI%) to BSP for each group to highlight the significance:

 

 

Now we can see the significance of a 1.6% difference in win strike rates – the returns are over 7p in the £ worse at Grade 1 tracks for these shorter priced runners compared with the non-Grade 1 tracks. Indeed, away from the top tracks we see a situation where one would have virtually broken even backing every single drifter to BSP when it opened at 4/1 or shorter.

Whatever is occurring to create these differences between Grade 1 tracks and non-Grade 1 tracks for drifters, I am not sure. It may be connected with average field size; it may be connected with the quality of racing. It could be a combination of those, or neither.

Sometimes it is not worth speculating, especially as in this case it is nigh on impossible to isolate why. I’m happy on this one that it makes sense to just go with the data.

Before moving on I have checked the 2023 data (up to 27^th Sept) and the same pattern for horses that drift/lengthen in price having opened 4/1 or shorter has continued:

 

 

The message according to all the information at my disposal is clear: horses which open at 4/1 or shorter and drift look to be POOR value when racing at Grade 1 tracks; away from these top tracks, such horses seem much better value – taking 2023 into account, going back to 2018 these runners would have lost you just 5p for every £100 bet.

 

Horses whose opening show price was 2/1 or shorter

Going back to data from ALL courses, if we focus on a shorter opening odds criterion of 2/1 or lower, and only look at drifters, we almost get to a break-even scenario. There were 7696 qualifiers of which 2801 won (SR 36.4%). Backing all 7696 runners at £1 stakes to BSP would have lost a meagre £49.13 (ROI -0.6%).

 

Horses whose opening show price was 2/1 or shorter that lengthened in price

If we once again look at the Grade 1 track data compared with other tracks for this subset of drifters, we see the following:

 

 

A similar, if stronger, pattern than with the 4/1 or shorter opening show cohort of drifters. Here, we are looking at a nearly 3% difference in win strike rate which equates to a difference of over 11p in the £ in terms of BSP returns.

As per the table above, drifters at non-Grade 1 tracks opening 2/1 or shorter have edged into profit. For this to happen across such a large sample – over 6500 runners – is interesting and impressive.

 

Horses whose opening show price was between 9/2 and 9/1

Time to look at the data for a bigger odds bracket. Here are the splits for each subset of the cohort whose opening show price was between 9/2 and 9/1:

 

 

It should have been no surprise to see those shortening in price winning more in percentage terms once again. In terms of returns, as with the shorter priced runners, horses that have shortened have been the worst value, albeit by just over 1p in the £.

 

Horses whose opening show price was between 9/2 and 9/1 that lengthened in price

I wanted to continue the comparison between drifters in this price bracket at Grade 1 and non-Grade 1 tracks to see if we get a similar differential as before. I assumed we would, as my expectations were that it would only start to reverse with longer-priced runners:

 

 

As before the non-Grade 1 track data is notably better, both in strike rate terms and BSP returns. However, the gap is starting to narrow, though the difference between the two is still clear. This dynamic has to switch around for bigger-priced runners and we will see whether this is the case shortly.

 

Horses whose opening show price was 10/1 or bigger

Onto double figure priced runners on the opening show now. Here are the results:

 

 

Horses that remained the same price have provided the best returns, while those shortening have marginally out-performed drifters. All groups though show poorer returns than the shorter priced runners we reviewed earlier. Both the shorteners and the drifters offered poor value for the punter.

 

Horses whose opening show price was 10/1 or bigger that lengthened in price

Finally for this section, I wanted to investigate whether this subset of drifters produced converse results whereby horses that raced at Grade 1 tracks performed better than those which did not.

 

 

Here, necessarily, we have the big switch around: horses racing at Grade 1 tracks have the better strike rate for the first time and their returns are much better than their non-Grade 1 track counterparts.

When comparing the results of horses running at a different level of racetrack, splitting up the drifters’ data into opening show price bands has been an eye opener for me. In the future, if my plan is to place my bet late at a Grade 1 track and my horse opens up 9/1 or shorter, I would think twice about backing it if it started to drift. Conversely if I was planning the same at a non-Grade 1 track then I would want to see it drift!

As it stands, the research shared so far has been very general – hence the huge sample sizes. I have not yet considered how much the price has changed, because clearly a horse can drift from 6/1 to 13/2, but another 6/1 shot could drift dramatically out to 10/1 and beyond. In a follow-up article I will be digging deeper into the size of the change in price.

Back to this article and, having looked at the splits in terms of strike rate and returns for different price bands, I thought it would be interesting to go back to where this all started and look at the percentage of all runners that either shorten in price, stay the same or lengthen/drift within each of these bands. Here are my findings:

 

 

This is very enlightening as we can see that the percentage of horses that drifted compared to horses that shortened is similar in the 4/1 or less group, and also in the 9/2 to 9/1 group (green/yellow bars). However, in the 10/1+ group, 42% of all runners drifted, compared to a much lower 28.9% of runners who shortened. These stats are implying that we should delay wagering longer-priced runners by either waiting to the last minute or simply using Betfair SP. For horses that open at prices of 9/1 or shorter, the timing of bet placement seems generally less crucial.

 

Trainers

Changing tack, a quick look at some raw trainer data now. I have chosen 25 high volume flat trainers, and I am simply comparing win strike rates and A/E indices for all of their runners within the three cohorts we’ve used throughout this piece – horses that shortened, horses that stayed the same price and horses that drifted. I have highlighted A/E indices of 0.95 or higher (in green) – these are essentially positive. A/E indices of 0.79 or lower (in red) are essentially negative:

 

 

There are more greens than reds and, as a rule, the strike rates increase as you read across the columns left to right. This is what we would expect based on the overall data presented earlier. However, George Boughey is interesting as his three strike rates sit very close together, between 17.25 and 17.72%. Horses of his that have drifted have proved much better value than those that have shortened.

Clive Cox has a poor record with horses that drift in price as does James Tate, perhaps suggesting these yards know when to bet! Meanwhile, David Menuisier has done extremely well with horses that have shortened in price. They would have provided you with returns of over 17p in the £ to BSP which is impressive: another yard to follow when they’re fancied maybe?

I wanted to delve a little more deeply into trainer statistics and analyse the percentage of runners for individual trainers that either shorten, stay the same price or lengthen.

Below is a list of trainers whose runners drift far more than they. I have ordered them by highest percentage of runners that lengthen in price:

 

 

It was surprising to see George Boughey in the list and even more surprising to see him at the top. I also had not expected to see Sir Mark Prescott or Gary Moore appear either. It may be that these horses are often put in at defensively short prices on the opening show, bookmakers fearful of shrewd trainers/connections landing a gamble. Elsewhere, some less well-known trainers are arguably more predictable entries in the table.

There are not many trainers where this scenario is reversed with the percentage of horses that shorten in price being higher than the percentage that drift. However, five well known handlers have this profile and are shown below:

 

 

There are some big guns in this list. Punters are aware of the skills of these trainers and hence their runners are usually going to be strong in the betting market. It may be that these yards are, generally speaking, less inclined to gamble their horses, though in the case of Aidan O’Brien that’s not typically the case.

*

It is time to wind up this first article into market movement. There are plenty of stats to chew over and hopefully for punters who bet near or around ‘the off’ it has given some useful data to potentially improve your profit/loss bottom line. You can read part two of this article here.

- DR

Other Recent Posts by This Author:

• More on Price Movement from Opening Show
• A Study of Owners in UK Flat Racing, Part 2
• A Study of Owners in UK Flat Racing, Part 1
• Seeking Value with Female Flat Jockeys
• Early Odds to Opening Odds to Starting Price