Dockage fee isn't clear

[Kaldari]

This is a minor thing, but the dockage fees are a bit confusing at first.
The "Facilities fee (/hr)" is straight forward enough, it's an hourly fee (11.83 for me), but what does the "Dockage (Length-Over-All/hr) mean, as it is also an hourly fee (479.23 for me)

[tritton82]

It's your berthing fee based on ship size. Where the facilities fee covers stuff like air exchange and airlock access your Dockage is your actual parking fee, and because there isn't a standard parking space size, the larger the ship, the higher the fee!

[Kaldari]

I suspected it was related to the ship size, and intend keeping an eye on it as I expand and upgrade, because it's vague about what it's actually referring to.

Is it:
- overall length (from bow to stern)
- mass, so as few items as possible, no internal walls, and throw out the kitchen sink
- volume (or block 'footprint' since it's overhead view), so it doesn't matter how the interior looks, just as long as the ship hull itself is as small as possible

And how does the cost scale up is important too. 500 dollars an hour is easy enough to pay, but it could be annoying to spend time building, only to find docking is prohibitively expensive

[tritton82]

Unfortunately I don't spend enough time docked at OKLG to say for sure. Given the name I'd assume overall length.

[Kaldari]

That would indeed be a logical assumption. While salvaging I had spent some time 'squaring off' my ship, without changing length nor width, to see how/if that would affect the fee.
But then I was distracted by a nearby derelict, which turns out to be quite juicy, so I'm still out in the black

I see on the nav screen though, that the "CURRENT TRG" information includes a line showing "D: size x size", so perhaps the fee is derived from that somehow

Update: After several distractions I have managed to return (drifted over 1000km while salvaging) to dock with my squared off ship. I'm 99% sure I haven't gone beyond my initial 'box size' and dockage is now 516.10/hr.
So dockage fees seem based around ship footprint, and are easily affordable