Schedule variance is defined as the difference between earned value and planned value. Some of the factors that can affect schedule variance are mostly contingencies such as: a worker can become ill or severely injured from the project, a vendor that you are relying on has made a delayed shipment, issues with management. If a worker is injured or has become severely ill, this can reduce your schedule variance in value because you are now required to find a worker to replace him/her and that could take some time. Thus, your entire project could be delayed because you have to spend time to look for a suitable replacement, and you need all of your workers to proceed. Your earned value will decrease due to lost time;therefore, your schedule variance could become negative, which means behind schedule. A vendor may have delivered a ship of materials late, which means that your workers were not able to continue working since they don’t have the raw materials. This will affect your earned value simply because your planned value is expected to be higher for that day, but your workers weren’t able to meet the expectations. Management can make a mistake in managing funds for the project or may have issues with sharing project team members with other leaders.