Where allowance for both the loading and discharging ports are added and calculated together. Either the contract may openly be on ‘reversible’ terms without actually stating so – e.g. 7 days, ‘all purposes’, or ’16 total days’ – or there may be an express clause giving the charterers the right or the option to apply reversible conditions if they so wish – in other words, if they calculate it to be in their favour to do so. Thus any laytime saved from the loading ports can be carried forward and added to laytime allowed at the port(s) of discharge. Average Laytime: Arises where separate calculations are performed for the loading and for the discharging ports, with the final results for each being combined in order to assess what is finally due – e.g. 2 days demurrage at load port would be cancelled out by 2 days despatch at discharge port, even though the daily value of demurrage may be twice that of despatch. At first sight it may appear there is no difference between the application of reversible and average laytime. In fact, differences can arise and, with the same basic facts, it is possible to reach three different results by applying each of the above alternatives. Laytime Definitions: ‘VOYLAY Rules 1993’ in which laytime terms have been defined by a group of distinguished international shipping practitioners. It may be found useful in everyday laytime calculating. One word of warning, however. The definitions relate to international practice and not necessarily to a particular code of law. Thus there may be slight but significant differences between the definition appearing in this document from legal practice in a particular country. It should also be noted that the rules do not automatically apply to every fixture made. Willing parties can however ensure that this is so by merely adding a short clause to the effect that in the event of a dispute the Voylay rules are to apply in interpreting particular words or phrases.