{"id":1465,"date":"2018-02-20T15:20:26","date_gmt":"2018-02-20T14:20:26","guid":{"rendered":"http:\/\/www.primanedacademy.com\/?p=1465"},"modified":"2018-06-11T16:03:01","modified_gmt":"2018-06-11T14:03:01","slug":"correctly-interpreting-activity-duration","status":"publish","type":"post","link":"https:\/\/www.primanedacademy.com\/en\/correctly-interpreting-activity-duration\/","title":{"rendered":"Correctly interpreting Activity Duration in Primavera P6"},"content":{"rendered":"

Duration and Calendar Duration, Time and Units\/Time explained, P6 basic.<\/em><\/p>\n

Time is of the essence. Both in project control and in our personal lives. As we\u2019ve been dealing with time since childhood, you would assume we have learned to communicate on it effectively and unambiguously. But when someone says: \u201cthis activity is going to take 48 hours\u201d you might take that as 2 days while he might\u2019ve meant it will take two persons 3 8-hour-working days to complete.<\/p>\n

\"\"<\/p>\n

In this post, I\u2019ll explain some terminology. What is an activity duration? How should we interpret it? Is there a difference with an assignment duration? How are calculations of duration being done in Primavera?<\/p>\n

Calendar duration<\/strong>
\nFor some people, there is only 1 kind of duration. It\u2019s called calendar duration and can be defined as follows:<\/p>\n

\u201cthe estimated total time between the start and the end of an activity\u201d.<\/p>\n

\"\"<\/p>\n

You can simply count it or you can calculate for example that an activity spanning from march (3rd month) to November (11th month) has a calendar duration of 9 months.<\/p>\n

\"\"<\/p>\n

Although normal human being are used to always count in calendar days, it is less used in Project management. In MSProject you can explicitly specify an activities calendar duration in \u2018elapsed days\u2019. In Primavera, calendar days are nowhere calculated or shown.<\/p>\n

Activity duration<\/strong>
\nIn project controls the term \u2018duration\u2019 by default purports \u2018Activity duration\u2019. Though that sounds like a very central concept, it is often poorly understood. The following definition can be found:<\/p>\n

\u201cThe estimated time required to complete an activity\u201d.<\/p>\n

This duration is different from the calendar duration as it is independent of the timeframe with its holiday exceptions or availability of resources.<\/p>\n

\"\"<\/p>\n

If you don\u2019t have any calendar restrictions, e.g. working 24 hours per day and 365 days per year, an activities\u2019 \u2018duration\u2019 and \u2018calendar duration\u2019 are the same in number of hours. Adding restrictions can augment the calendar duration while they don\u2019t affect the activity duration.<\/p>\n

Duration is usually expressed in (working) days, though in some occasions it can be (working) hours, weeks, months or even years. In the example below we can say that the activity has a duration of 8 days but it can also be declared as 1.6 weeks. To convert between these units we need to decide how many working days there are in a normal working week, which in Primavera is set in the calendar settings.<\/p>\n

\"\"<\/p>\n

The formula for primavera looks like this:<\/p>\n

\"\"<\/p>\n

Note that in Primavera the smallest step in calendar availability is half an hour so the above formula also works with counting half-hours instead of seconds.<\/p>\n

Assignment duration<\/strong>
\nFinally, we also have \u2018assignment duration\u2019. Its definition is very similar to that of an activity duration:<\/p>\n

\u201cThe estimated time required to complete an assignment<\/p>\n

An assignment duration can be calculated by the amount of resources to be processed and the speed in which they are processed.<\/p>\n

\"\"<\/p>\n

\"\"<\/p>\n

 <\/p>\n

Activities however can have multiple assignments and they can have different durations. In primavera, only the assignment with the longest duration leads the activity duration. It also goes the other way around. If you change the activity duration, the duration of the longest assignment will change as well. This leads up to the following model:<\/p>\n

\"\"<\/p>\n

Example<\/strong>
\nLet\u2019s further illustrate the different terms by an example.<\/p>\n

In the example, an activity spans from 9 a.m. Wednesday until Monday 3 p.m. In this time period, it is being executed during the weekdays from 9.a.m. until 5 p.m. continuously by two men (2FTE\u2019s).<\/p>\n

The Units\/time, Units, Assignment Duration, Duration and Calendar Duration are then as follows:<\/p>\n

\"\"<\/p>\n

Conclusion<\/strong>
\nTo wrap it up an hour isn\u2019t just an hour. You\u2019ve got calendar hours for your calendar duration, work-hours for your activity or assignment duration and even man-hours for your units. Knowing that there is a difference is the most important step before implementing a schedule.<\/p>\n

To be honest I tried to keep things simple and there\u2019s still more to all of this then mentioned in this post. Assignment durations can be longer than activity durations if you start working with \u2018Resource Dependent\u2019 activities. Calendar durations can be smaller than your activity durations, while units\/time show incorrect values. We\u2019ll talk about that in a different post.<\/p>\n

This blog is originally placed on\u00a0Primaned.be<\/a>\u00a0op 20 December 2017.<\/strong><\/p>\n","protected":false},"excerpt":{"rendered":"

Duration and Calendar Duration, Time and Units\/Time explained, P6 basic. Time is of the essence. Both in project control and in our personal lives. As we\u2019ve been dealing with time since childhood, you would assume we have learned to communicate on it effectively and unambiguously. But when someone says: \u201cthis activity is going to take […]<\/p>\n","protected":false},"author":11,"featured_media":1473,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[87],"tags":[136,91],"class_list":["post-1465","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog-en","tag-oracle-primavera","tag-primaned-academy-en"],"acf":[],"yoast_head":"\nCorrectly interpreting Activity Duration in Primavera P6 - Primaned Academy<\/title>\n<meta name=\"description\" content=\"Duration and Calendar Duration, Time and Units\/Time explained, P6 basic. Time is of the essence. Both in project control and in our personal lives.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.primanedacademy.com\/en\/correctly-interpreting-activity-duration\/\" \/>\n<meta property=\"og:locale\" content=\"en_GB\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Correctly interpreting Activity Duration in Primavera P6 - Primaned Academy\" \/>\n<meta property=\"og:description\" content=\"Duration and Calendar Duration, Time and Units\/Time explained, P6 basic. Time is of the essence. Both in project control and in our personal lives.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.primanedacademy.com\/en\/correctly-interpreting-activity-duration\/\" \/>\n<meta property=\"og:site_name\" content=\"Primaned Academy\" \/>\n<meta property=\"article:published_time\" content=\"2018-02-20T14:20:26+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2018-06-11T14:03:01+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.primanedacademy.com\/wp-content\/uploads\/Activity-Duration-afbeelding-8.png\" \/>\n\t<meta property=\"og:image:width\" content=\"725\" \/>\n\t<meta property=\"og:image:height\" content=\"516\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/png\" \/>\n<meta name=\"author\" content=\"Matthias van Campen\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Matthias van Campen\" \/>\n\t<meta name=\"twitter:label2\" content=\"Estimated reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"4 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/www.primanedacademy.com\\\/en\\\/correctly-interpreting-activity-duration\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/www.primanedacademy.com\\\/en\\\/correctly-interpreting-activity-duration\\\/\"},\"author\":{\"name\":\"Matthias van Campen\",\"@id\":\"https:\\\/\\\/www.primanedacademy.com\\\/#\\\/schema\\\/person\\\/d2959048c95258f3a51f8eb6c203ce08\"},\"headline\":\"Correctly interpreting Activity Duration in Primavera P6\",\"datePublished\":\"2018-02-20T14:20:26+00:00\",\"dateModified\":\"2018-06-11T14:03:01+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/www.primanedacademy.com\\\/en\\\/correctly-interpreting-activity-duration\\\/\"},\"wordCount\":729,\"image\":{\"@id\":\"https:\\\/\\\/www.primanedacademy.com\\\/en\\\/correctly-interpreting-activity-duration\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/www.primanedacademy.com\\\/wp-content\\\/uploads\\\/Activity-Duration-afbeelding-8.png\",\"keywords\":[\"Oracle Primavera\",\"Primaned Academy\"],\"articleSection\":[\"Blog - EN\"],\"inLanguage\":\"en-GB\"},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/www.primanedacademy.com\\\/en\\\/correctly-interpreting-activity-duration\\\/\",\"url\":\"https:\\\/\\\/www.primanedacademy.com\\\/en\\\/correctly-interpreting-activity-duration\\\/\",\"name\":\"Correctly interpreting Activity Duration in Primavera P6 - Primaned Academy\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/www.primanedacademy.com\\\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/www.primanedacademy.com\\\/en\\\/correctly-interpreting-activity-duration\\\/#primaryimage\"},\"image\":{\"@id\":\"https:\\\/\\\/www.primanedacademy.com\\\/en\\\/correctly-interpreting-activity-duration\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/www.primanedacademy.com\\\/wp-content\\\/uploads\\\/Activity-Duration-afbeelding-8.png\",\"datePublished\":\"2018-02-20T14:20:26+00:00\",\"dateModified\":\"2018-06-11T14:03:01+00:00\",\"author\":{\"@id\":\"https:\\\/\\\/www.primanedacademy.com\\\/#\\\/schema\\\/person\\\/d2959048c95258f3a51f8eb6c203ce08\"},\"description\":\"Duration and Calendar Duration, Time and Units\\\/Time explained, P6 basic. Time is of the essence. Both in project control and in our personal lives.\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/www.primanedacademy.com\\\/en\\\/correctly-interpreting-activity-duration\\\/#breadcrumb\"},\"inLanguage\":\"en-GB\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/www.primanedacademy.com\\\/en\\\/correctly-interpreting-activity-duration\\\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"en-GB\",\"@id\":\"https:\\\/\\\/www.primanedacademy.com\\\/en\\\/correctly-interpreting-activity-duration\\\/#primaryimage\",\"url\":\"https:\\\/\\\/www.primanedacademy.com\\\/wp-content\\\/uploads\\\/Activity-Duration-afbeelding-8.png\",\"contentUrl\":\"https:\\\/\\\/www.primanedacademy.com\\\/wp-content\\\/uploads\\\/Activity-Duration-afbeelding-8.png\",\"width\":725,\"height\":516},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/www.primanedacademy.com\\\/en\\\/correctly-interpreting-activity-duration\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/www.primanedacademy.com\\\/en\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Correctly interpreting Activity Duration in Primavera P6\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/www.primanedacademy.com\\\/#website\",\"url\":\"https:\\\/\\\/www.primanedacademy.com\\\/\",\"name\":\"Primaned Academy\",\"description\":\"Opleidingen in Projectbeheersing \\\/ Project Controls\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/www.primanedacademy.com\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-GB\"},{\"@type\":\"Person\",\"@id\":\"https:\\\/\\\/www.primanedacademy.com\\\/#\\\/schema\\\/person\\\/d2959048c95258f3a51f8eb6c203ce08\",\"name\":\"Matthias van Campen\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-GB\",\"@id\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/edfb18d6c6976f027ea2efaa7aa7f2423dbd8a7fccd98e37db40ed0702d24560?s=96&d=mm&r=g\",\"url\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/edfb18d6c6976f027ea2efaa7aa7f2423dbd8a7fccd98e37db40ed0702d24560?s=96&d=mm&r=g\",\"contentUrl\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/edfb18d6c6976f027ea2efaa7aa7f2423dbd8a7fccd98e37db40ed0702d24560?s=96&d=mm&r=g\",\"caption\":\"Matthias van Campen\"},\"url\":\"https:\\\/\\\/www.primanedacademy.com\\\/en\\\/author\\\/matthias-van-campen\\\/\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Correctly interpreting Activity Duration in Primavera P6 - Primaned Academy","description":"Duration and Calendar Duration, Time and Units\/Time explained, P6 basic. Time is of the essence. Both in project control and in our personal lives.","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.primanedacademy.com\/en\/correctly-interpreting-activity-duration\/","og_locale":"en_GB","og_type":"article","og_title":"Correctly interpreting Activity Duration in Primavera P6 - Primaned Academy","og_description":"Duration and Calendar Duration, Time and Units\/Time explained, P6 basic. Time is of the essence. Both in project control and in our personal lives.","og_url":"https:\/\/www.primanedacademy.com\/en\/correctly-interpreting-activity-duration\/","og_site_name":"Primaned Academy","article_published_time":"2018-02-20T14:20:26+00:00","article_modified_time":"2018-06-11T14:03:01+00:00","og_image":[{"width":725,"height":516,"url":"https:\/\/www.primanedacademy.com\/wp-content\/uploads\/Activity-Duration-afbeelding-8.png","type":"image\/png"}],"author":"Matthias van Campen","twitter_card":"summary_large_image","twitter_misc":{"Written by":"Matthias van Campen","Estimated reading time":"4 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/www.primanedacademy.com\/en\/correctly-interpreting-activity-duration\/#article","isPartOf":{"@id":"https:\/\/www.primanedacademy.com\/en\/correctly-interpreting-activity-duration\/"},"author":{"name":"Matthias van Campen","@id":"https:\/\/www.primanedacademy.com\/#\/schema\/person\/d2959048c95258f3a51f8eb6c203ce08"},"headline":"Correctly interpreting Activity Duration in Primavera P6","datePublished":"2018-02-20T14:20:26+00:00","dateModified":"2018-06-11T14:03:01+00:00","mainEntityOfPage":{"@id":"https:\/\/www.primanedacademy.com\/en\/correctly-interpreting-activity-duration\/"},"wordCount":729,"image":{"@id":"https:\/\/www.primanedacademy.com\/en\/correctly-interpreting-activity-duration\/#primaryimage"},"thumbnailUrl":"https:\/\/www.primanedacademy.com\/wp-content\/uploads\/Activity-Duration-afbeelding-8.png","keywords":["Oracle Primavera","Primaned Academy"],"articleSection":["Blog - EN"],"inLanguage":"en-GB"},{"@type":"WebPage","@id":"https:\/\/www.primanedacademy.com\/en\/correctly-interpreting-activity-duration\/","url":"https:\/\/www.primanedacademy.com\/en\/correctly-interpreting-activity-duration\/","name":"Correctly interpreting Activity Duration in Primavera P6 - Primaned Academy","isPartOf":{"@id":"https:\/\/www.primanedacademy.com\/#website"},"primaryImageOfPage":{"@id":"https:\/\/www.primanedacademy.com\/en\/correctly-interpreting-activity-duration\/#primaryimage"},"image":{"@id":"https:\/\/www.primanedacademy.com\/en\/correctly-interpreting-activity-duration\/#primaryimage"},"thumbnailUrl":"https:\/\/www.primanedacademy.com\/wp-content\/uploads\/Activity-Duration-afbeelding-8.png","datePublished":"2018-02-20T14:20:26+00:00","dateModified":"2018-06-11T14:03:01+00:00","author":{"@id":"https:\/\/www.primanedacademy.com\/#\/schema\/person\/d2959048c95258f3a51f8eb6c203ce08"},"description":"Duration and Calendar Duration, Time and Units\/Time explained, P6 basic. Time is of the essence. Both in project control and in our personal lives.","breadcrumb":{"@id":"https:\/\/www.primanedacademy.com\/en\/correctly-interpreting-activity-duration\/#breadcrumb"},"inLanguage":"en-GB","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.primanedacademy.com\/en\/correctly-interpreting-activity-duration\/"]}]},{"@type":"ImageObject","inLanguage":"en-GB","@id":"https:\/\/www.primanedacademy.com\/en\/correctly-interpreting-activity-duration\/#primaryimage","url":"https:\/\/www.primanedacademy.com\/wp-content\/uploads\/Activity-Duration-afbeelding-8.png","contentUrl":"https:\/\/www.primanedacademy.com\/wp-content\/uploads\/Activity-Duration-afbeelding-8.png","width":725,"height":516},{"@type":"BreadcrumbList","@id":"https:\/\/www.primanedacademy.com\/en\/correctly-interpreting-activity-duration\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.primanedacademy.com\/en\/"},{"@type":"ListItem","position":2,"name":"Correctly interpreting Activity Duration in Primavera P6"}]},{"@type":"WebSite","@id":"https:\/\/www.primanedacademy.com\/#website","url":"https:\/\/www.primanedacademy.com\/","name":"Primaned Academy","description":"Opleidingen in Projectbeheersing \/ Project Controls","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.primanedacademy.com\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-GB"},{"@type":"Person","@id":"https:\/\/www.primanedacademy.com\/#\/schema\/person\/d2959048c95258f3a51f8eb6c203ce08","name":"Matthias van Campen","image":{"@type":"ImageObject","inLanguage":"en-GB","@id":"https:\/\/secure.gravatar.com\/avatar\/edfb18d6c6976f027ea2efaa7aa7f2423dbd8a7fccd98e37db40ed0702d24560?s=96&d=mm&r=g","url":"https:\/\/secure.gravatar.com\/avatar\/edfb18d6c6976f027ea2efaa7aa7f2423dbd8a7fccd98e37db40ed0702d24560?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/edfb18d6c6976f027ea2efaa7aa7f2423dbd8a7fccd98e37db40ed0702d24560?s=96&d=mm&r=g","caption":"Matthias van Campen"},"url":"https:\/\/www.primanedacademy.com\/en\/author\/matthias-van-campen\/"}]}},"_links":{"self":[{"href":"https:\/\/www.primanedacademy.com\/en\/wp-json\/wp\/v2\/posts\/1465","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.primanedacademy.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.primanedacademy.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.primanedacademy.com\/en\/wp-json\/wp\/v2\/users\/11"}],"replies":[{"embeddable":true,"href":"https:\/\/www.primanedacademy.com\/en\/wp-json\/wp\/v2\/comments?post=1465"}],"version-history":[{"count":4,"href":"https:\/\/www.primanedacademy.com\/en\/wp-json\/wp\/v2\/posts\/1465\/revisions"}],"predecessor-version":[{"id":2376,"href":"https:\/\/www.primanedacademy.com\/en\/wp-json\/wp\/v2\/posts\/1465\/revisions\/2376"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.primanedacademy.com\/en\/wp-json\/wp\/v2\/media\/1473"}],"wp:attachment":[{"href":"https:\/\/www.primanedacademy.com\/en\/wp-json\/wp\/v2\/media?parent=1465"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.primanedacademy.com\/en\/wp-json\/wp\/v2\/categories?post=1465"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.primanedacademy.com\/en\/wp-json\/wp\/v2\/tags?post=1465"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}