Tested on Samsung S6 Android 6.0.1 and Samsung J7 Android 7.0.0 using the latest Canary #67.0.3363.3 and not able to observe the negative values with '-' before the values.

marcin@ -- Thanks for reporting the issue. Could you please share the logs related to this issue. 

Requesting dev team to take a look into this issue.

Thanks in advance!

Thank you for reporting this. This seems to be a bug in our code.

Assigning to rajendrant@ since it's related to data usage and site breakdown. The fix should be merged back to M-65.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/0f8f470d2e182759b8f505925a6ae9073d3befa9

commit 0f8f470d2e182759b8f505925a6ae9073d3befa9
Author: rajendrant <rajendrant@chromium.org>
Date: Thu Mar 08 01:41:06 2018

Fix overflow in data saver remaining sites data usage

Bug:  818520 
Change-Id: I6a5c98239f05caf3499ac6eb5de520160ae1bed0
Reviewed-on: https://chromium-review.googlesource.com/953202
Reviewed-by: Tarun Bansal <tbansal@chromium.org>
Reviewed-by: Theresa <twellington@chromium.org>
Commit-Queue: rajendrant <rajendrant@chromium.org>
Cr-Commit-Position: refs/heads/master@{#541680}
[modify] https://crrev.com/0f8f470d2e182759b8f505925a6ae9073d3befa9/chrome/android/java/src/org/chromium/chrome/browser/preferences/datareduction/DataReductionSiteBreakdownView.java

This is a simple fix to merge.

This bug requires manual review: Request affecting a post-stable build
Please contact the milestone owner if you have questions.
Owners: cmasso@(Android), cmasso@(iOS), bhthompson@(ChromeOS), govind@(Desktop)

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Sorry, I meant merge to M-66.

Please verify in Canary

still not enough / not fixed

Deleted: Screenshot_20180310-133943.png 486 KB

	Screenshot_20180310-133943.png 486 KB View Download

Please merge this change as soon as possible

This issue has been approved for a merge. Please merge the fix to any appropriate branches as soon as possible!

If all merges have been completed, please remove any remaining Merge-Approved labels from this issue.

Thanks for your time! To disable nags, add the Disable-Nags label.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Raj, looks like you also need to remove the int cast here: 

https://cs.chromium.org/chromium/src/chrome/android/java/src/org/chromium/chrome/browser/preferences/datareduction/DataReductionSiteBreakdownView.java?l=236-238&rcl=008fe2b619f03355652b8988c1724f22e342c6b0

Thanks Robert. I will remove.

Looks like a different CL has added that cast.
https://chromium-review.googlesource.com/953181

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/c51a0eb99240cd68c7a5a5235330ec4c8f1cd98d

commit c51a0eb99240cd68c7a5a5235330ec4c8f1cd98d
Author: rajendrant <rajendrant@chromium.org>
Date: Mon Mar 19 20:59:10 2018

Fix int cast in data saver remaining sites data usage

Bug:  818520 
Change-Id: Id9a9c289a29ab9b1ccef5eff4f0019bb47363866
Reviewed-on: https://chromium-review.googlesource.com/969452
Reviewed-by: Theresa <twellington@chromium.org>
Commit-Queue: rajendrant <rajendrant@chromium.org>
Cr-Commit-Position: refs/heads/master@{#544154}
[modify] https://crrev.com/c51a0eb99240cd68c7a5a5235330ec4c8f1cd98d/chrome/android/java/src/org/chromium/chrome/browser/preferences/datareduction/DataReductionSiteBreakdownView.java

This issue has been approved for a merge. Please merge the fix to any appropriate branches as soon as possible!

If all merges have been completed, please remove any remaining Merge-Approved labels from this issue.

Thanks for your time! To disable nags, add the Disable-Nags label.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/6bf131cc74a8f0d9da053aaf7aff9a414f80b552

commit 6bf131cc74a8f0d9da053aaf7aff9a414f80b552
Author: rajendrant <rajendrant@chromium.org>
Date: Tue Mar 20 21:33:50 2018

Fix overflow in data saver remaining sites data usage

Bug:  818520 
Change-Id: I6a5c98239f05caf3499ac6eb5de520160ae1bed0
Reviewed-on: https://chromium-review.googlesource.com/953202
Reviewed-by: Tarun Bansal <tbansal@chromium.org>
Reviewed-by: Theresa <twellington@chromium.org>
Commit-Queue: rajendrant <rajendrant@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#541680}(cherry picked from commit 0f8f470d2e182759b8f505925a6ae9073d3befa9)
Reviewed-on: https://chromium-review.googlesource.com/972301
Reviewed-by: rajendrant <rajendrant@chromium.org>
Cr-Commit-Position: refs/branch-heads/3359@{#356}
Cr-Branched-From: 66afc5e5d10127546cc4b98b9117aff588b5e66b-refs/heads/master@{#540276}
[modify] https://crrev.com/6bf131cc74a8f0d9da053aaf7aff9a414f80b552/chrome/android/java/src/org/chromium/chrome/browser/preferences/datareduction/DataReductionSiteBreakdownView.java

Verified in latest canary.