Sebastian Vettel's ultrasoft run on the second day of this week's Barcelona Formula 1 test may have been the benchmark for the week, but the timesheets rarely tell the full story of what's going on.

By: Jonathan Noble, Formula 1 Editor

Sebastian Vettel's ultrasoft run on the second day of this week's Barcelona Formula 1 test may have been the benchmark for the week, but the timesheets rarely tell the full story of what's going on.

Indeed, variations in fuel load, test programmes and tyre compounds mean that invariably some calculations are needed to work our a clearer picture.

But, although cars are not yet in their final configuration so it is too early to make firm predictions for Melbourne, it is possible to get an idea of what trends have been taking place so far.

Testing maths

One thing that we can do is calculate what times would have been possible by cars and drivers if they had opted to run on the better tyre compounds.

Using historical data of the performance gaps between the different compounds, allied to live data delivered from this week's test, we can extrapolate what potential there is in each car.

The actual time between the different tyre compounds does vary between cars, which makes it hard to deliver a totally accurate number, but we can at least get some indication of where things stand.

So using a mid-point calculation, we can estimate the ultrasoft is 0.6 seconds faster than the supersoft, which is 0.6 seconds faster than the soft, which is 1.1 seconds faster than the medium.

Applying those time differences to the best times from each car this week, means we can deduct lap times from those drivers who set times on harder compound.

In this case, we will deduct 0.6 seconds from a supersoft time, 1.2 seconds from a soft time and 2.3 seconds from a medium time.

This then gives us these leading times from the test if all drivers had run on the ultrasoft.

But a word of caution: we do not know what fuel loads cars were carrying when they set their best times – with 10kg of fuel being worth around 0.3 seconds per laps - so the reality is still likely to be a bit different.

Taking the best time logged by each car, this then gives us the running order.

 Force India  Nico Hulkenberg 1:22.510
 Mercedes  Nico Rosberg 1:22.567
 Ferrari  Sebastian Vettel 1:22.810
 Toro Rosso  Max Verstappen 1:23.093
 Red Bull  Daniel Ricciardo 1:23.525
 Sauber  Marcus Ericsson 1:24.037
 Renault  Kevin Magnussen 1:24.063
 Haas  Esteban Gutierrez 1:24.324
 Williams  Valtteri Bottas 1:24.448
 Manor  Pascal Wehrlein 1:24.725
 McLaren  Fernando Alonso 1:24.882

Do not read too much into the specifics of ranking, though, because beyond fuel loads the variation in tyre performance on each car can be around two tenths of a second too.

But while it is hard to be definitive, the clear trend is there: that Mercedes, during a week where it focused on pure reliability and system checks, was still able to deliver a time better than Ferrari which did some quick runs, is an ominous sign ahead of 2016.

Perhaps most intriguing, though, is what Force India has been up to. Sergio Perez had been adamant that the outfit was not showboating in testing, by pumping all the fuel out and going for a glory run.

His supersoft time was strong, and appears to show the team has made a step on from 2015 when it enjoyed an impressive end to the campaign.

All eyes will now be on what comes out in week two, when teams begin pushing the limits of the cars and we can get our first indication of just how the battle at the front is shaping up.

Gallery: Analysis: Ferrari tops times, but was it really the quickest car?