A cylindrical bar with $200$ mm diameter is being turned with a tool having geometry $0 ^\circ – 9 ^\circ -7^ \circ – 8^ \circ – 15^ \circ – 30^ \circ – 0.05$ inch (coordinate system, ASA) resulting in a cutting force $F_{c1}$. If the tool geometry is changed to $0^ \circ – 9^ \circ – 7^ \circ – 8^ \circ – 15^ \circ – 0^ \circ – 0.05$ inch (Coordinate system, ASA) and all other parameters remains unchanged, the cutting force changes to $F_{C2}$. Specific cutting energy (in $J/mm^3$) is $U_c = U_0(t_1)^{-0.4}$, where $U_0$ is the specific energy coefficient, and $t_1$ is the uncut thickness in mm. The value of percentage change in cutting force $F_{c2}$, i.e. $\displaystyle \bigg( \frac{F_{c2} – F_{c1}}{F_{c1}} \bigg) \times 100$, is ________ (round off to one decimal place)