My two cents
Here are a few tricks and tips that I have used in the past to end my presentations.
Make a one-slide visual summary
One way is to have a summary slide that includes all the main points, graphs, and numbers, similar to what Apple does in their keynotes when they present a new product.
Let people know what’s the one thing they should remember
Another way is to focus on one key element that people must remember. For example, you can write a sentence that starts with:
"If you have to remember one thing, remember this…”
And end the sentence with the most important point you want your audience to take away.
Suggest questions
You can also suggest questions for the audience to ask you instead of ending the presentation.
Write down questions that you feel comfortable answering, and that would be a good addition to what you have presented. This can help steer the conversation towards something that you find helpful.
Finish before the time
As a bonus, try finishing your presentation before the time you were given.
This might be unique to the Swiss culture, but if you take less time than what people have given you, usually the audience is appreciative that you not only respected their time but also gave them extra time back.