# Account balance utilisation

This is categorised as an [account metric](/xnUSdbbaQS-wn0KmIYRh-Q).

The 'utilisation' of $M_i$'s account can be defined by normalising the [account balance](/R1iAIsZoRRmJgIV4NlHQZw) $b_i$ to the [account limits](/AYLZ5n-WTG6eiRVSlh0qOw), where $L_i^+$ is $M_i$'s' positive limit and $L_i^-$ the negative limit:

$$u_i^{\pm} = \frac{b_i}{L_i^{\pm}}
$$

Utilisation has the following properties:

* If $b_i = 0$ then $u_i^{\pm} = 0$;
* If $b_i = L_i^{\pm}$ then $u_i^{\pm} = 1$.

Utilisation can be calculated for both clearing and trading limits. Any member that has a clearing utilisation less than or equal to 1 at the end of their club's settlement period will not have to transact with the [system account](/spMD7anJS0uiuVoF2OXE2w) (see the 'System payment amounts' section in [late payment](/iIVkdpz_S76a_6FexHZWAw)). If a member's negative trading utilisation is consistently high over multiple settlement periods, this may serve as an indicator that they are imposing excessive risk on other members (see [account balance limits](/AYLZ5n-WTG6eiRVSlh0qOw) for more details) which could feed into [reputation metrics](/5FokSVvRSjChYIPN2PuhcA). Likewise, a consistently high positive trading utilisation suggests that extra suppliers within the network should be sought for that member.