The strikes began on the 8th, but no casualties. That's when the data for the chart begins

• https://www.aljazeera.com/news/2023/10/8/israel-hezbollah-exchange-fire-raising-regional-tensions

The next day, Hezbollah fired at Israel in response to Israel killing 3 Hezbollah members from bombardment of Southern Lebanon

The Lebanese armed group Hezbollah has fired a barrage of rockets into Israel after at least three of its members were killed during an Israeli bombardment of southern Lebanon amid soaring tensions on Israel’s northern border.

• https://www.aljazeera.com/news/2023/10/9/hezbollah-fires-on-israel-after-several-members-killed-in-shelling

• https://www.aljazeera.com/news/2023/10/10/rockets-fired-from-southern-lebanon-towards-israel-as-gaza-is-bombed

Previous strikes in October were in retaliation to assassination

• https://www.aljazeera.com/news/2024/9/18/hezbollah-and-israel-a-timeline-of-conflict

Before the assassination,

Until recently, the border had been relatively quiet. Occasional rockets or drones crossed from Lebanon into Israel without leading to serious escalation, while Israel violated Lebanese airspace more than 22,000 times from 2007 to 2022.

• https://www.aljazeera.com/news/2023/10/17/beyond-hezbollah-the-history-of-tensions-between-lebanon-and-israel