Same values causes different points on y-axis

I create a time-series-chart out of an InfluxDB database. In the example picture below I marked three points that all have the same y-value but the position on the y-axis is different. I expected a horizontal line for these three points.

Here is the InfluxDB query:
from(bucket: “Hive”)
|> range(start: v.timeRangeStart, stop: v.timeRangeStop)
|> filter(fn: (r) => r["_measurement"] == “mqtt_consumer”)
|> filter(fn: (r) => r["_field"] == “value”)
|> aggregateWindow(every: v.windowPeriod, fn: mean, createEmpty: false)
|> yield(name: “mean”)

What is the reason for that?

I found something by my own. The values in the InfluxDB are float values. The query Inspector of Grafana shows me also float values in the response. But the values in the charts are all rounded. The position on the y-axis seemed to be correct but the value that is showed when the mouse is over that point is rounded. For Example: Point on y-axis is 968.3 and it is show as 968.0.

I solved my problem after I changed the value of “Decimals” from “auto” to “3”.