‘Gather Data’ is the second step that you take in order to run a Retrospective meeting. The two techniques that can help with you gathering data are Timeline and Color Code Dots.
Timeline
Timeline is exactly what it sounds like. It is a way of displaying all of the meaningful activities that took place during the course of a sprint in chronological order. Each team member adds cards to the sprint timeline with the events that were significant to him or her. After an iteration, the team reviews the timeline and adds cards that might have been missed.

Color Code Dots
Color Code Dots are used alongwith the timeline so these aren’t two different techniques. These are used by the team members to indicate how they felt about all of the events on the timeline. The retrospective meeting moderator can provide colored dots to the team members which can represent their feelings for instance a green dot represents a positive feeling and a yellow dot represents a negative feeling. All team members go over the timeline and place those dots on the events to indicate whether they felt positive or negative during those activities.

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